_You have a few answers that tell you to back off immediately, that it is a joke or you are getting set up to be the "office mom". You have one answer that gives you a very concrete step by step guide on how to actually do it (only slightly tongue-in-cheek)._

_One caveat: if you simply do not want to do such a thing, are uncomfortable with the job itself, are afraid to talk with other people over the phone and such, then ignore this answer, go to your boss and just say no. If, on the other hand you have no problem with all of this, and are just unsure whether it will benefit or hurt your standing in the company, then read on._

Let me add a fully "pro party service" answer with zero tongue-in-cheek:

1. I have worked in 40-60 person companies, as well as in 10-15 person teams within much larger companies. I can very well see how such a bunch of people could all simply be technical folks who have no pleasure and no interest in organizing parties or other social events. There was never a dedicated "party organizer". Sometimes there were folks who did big events, but they would not really bother about small ones like a few people going to a bowling alley. So, there is, in my opinion, no immediate reason to suspect foul play.
2. I find it quite normal that a new person is asked to do this. They are not asking you to do table-dancing on the evening of the party, but they are asking you to manage a small project. Period. It does not matter that it is about merry-making. It could as well be a customer event or some other team-building event with real content (be glad that it is not!). It still needs professional conduct on your side. Your benefit is that it needs no previous knowledge about anything whatsoever, so you are likely as well suited as everybody else. 
3. The actual "doing" should be quite "doable" for you. It is a simple process - find a location, check out all the details, organize payment and such. Think of it like implementing an algorithm.
4. Be 100% sure about what you are *not* going to do. You are *not* going to hand-hold everybody to the alley. You are *not* going to serve drinks while there. You are *not* going to bring a cake that you baked at home. You are *not* going to do anything else than the other people at that evening. You can and should be upfront about this ("manage the expectations of your customer"). You organize the alley and maybe set up a Doodle to find out who is going to attend; you may help them distribute people into cars and such. You take all decisions that you reasonably can (everybody will be glad for every single point you decide instead of coming back to ask them). But you are *not* going to be a handmaiden for anyone here. This is important.
5. Make it so there is a clear "handoff" where the bowling alley is now in charge. I.e., your organizational job ends at the point of time where everybody stands at the alley entrance, right before you grab your shoes. After that, the alley personell will do the rest (whatever they do - take orders, bring food/drink etc.). You can easily hand over the process of managing the actual bowling (making teams and such) to someone who has bowling experience. You are *not* responsible for whatever happens after this point. And then enjoy the evening!
   * One remark on legalities: at least in my country, an organizer of an event has certain legal obligations. In your case, I would, at the *start* of the event, tell them in a sober way that your part is now officially over and they are on their own now ("behave yourself, I will not be held responsible for whatever happens now" - as tongue-in-cheek as necessary, but still plainly understandable). You should also give a time where the event officially ends (which should be at or before the time you intend to leave yourself). People are free to stay longer, but it will be 100% clear that they are not here on "business time".
   * Additionally, if your boss is there, then clearly put all responsibility in his hand ("I am not a bowling expert, so Mr. Xyz will take on from here as our official host of the evening."). After that, you clearly step back. Let him walk everybody into the alley and so on. Do that *before* you get your shoes, so, in case something really unlucky happens, everybody including the alley personell remembers who brought your troupe inside. 

While it may sound like a trivial setup to you, it may not be one. Being the guy (or girl) who can do such things in a company is not a sign that you are less worthy as a programmer. If you are afraid that you will always be the "girl" amongst the manly programmers and that they hence will think less of you, that may or may not be due to you organizing an event. But then you have a *much* larger problem than a bowling evening, anyways.

The benefits of being a person who can actually manage events on top of being a good programmer (or whatever job description you have) are plenty - and if you do this one right, you *will* get to do more events later. 

* It might transfer into managing customer events or earnest internal events eventually. That is not an easy job, it comes with standing, and everybody will be honestly glad to have you around.
* It will let you grow as a person; you get to "boss people around", you get to make decisions without having to refer to some lead developer all the time, and so on. If you do it well, it will be huge for your self-esteem. If you do it bad, you will get very direct feedback, which is not the worst that can happen to a human. Responsibility.
* If you are slightly uncomfortable doing the actual deeds (calling the alley, trying to organize an event and such), that is a great opportunity to work on that. Communication skills and organizational skills are always useful.
* If you do it right, people will simply like you for it, which isn't the worst, in any company. You will stand out a *lot*, and, unless you fail, in an undoubtedly positive way.
* Your CV will contain "event coordinator", letting you expand on that in case you later find out that you actually like that kind of work. Sure, you are seeing yourself as a programmer now, but there will be a time in 10, 20, 30 years when you are going to want to develop further. Starting out with relatively easy jobs on the side like this is a *very* smooth path to more earnest endeavours.