What is the benefit (besides obvious monetary savings by the company) of not allowing family members to attend team building events? Is this a common practice?
You need to face facts: In the scope of the workplace, your regular life family is not a part of that “team.”
Now you say this:
I am pretty confident half of the invited employees have never met…
Bingo! The purpose of “team building” events is to get a lot of disparate people together who work together in various capacities and get them to work together in a team. Basically, get everyone to know everyone in some way outside of the workplace that — key point — encourages you to bond with each other.
Now, some people there might be support staff you don’t deal with directly. But the point is your organization wants to make you feel that if/when you reach out to support staff that there is some kinship in place. Some respect for who people are and what they do and how they all work together.
However, there is a restriction I find to be quite odd: no family members are permitted, meaning spouses and kids are out of the picture.
Yes, exactly. Like I said before, goal is to build an organizational team. Not have a “meet and greet” with extraneous family members who might inadvertently interfere with the process.
Now I’m not saying your spouse and children will deliberately meddle, but the fact they are there at all might simply get in the way of co-workers being co-workers. For example, let’s say part of the team building includes co-workers being profoundly honest about how each other works? Who wants to say, “Look, I don’t think you are doing a good job…” while someone’s spouse and children are around?
You need to look at these “team building” sessions as a mini boot camp. Yeah, there are families and children on military bases. But they don’t show up at boot camp to cheer someone on, right? It’s only before and afterwards.
During “team building” there is nothing but you and other team members. And that is the way it goes.
Also, for some reason I glossed over this when I initially answered the question:
The company I work in is currently organizing an after-hours team building event, which consists of 4-5 hours of some kind of fun activity off-site.
4-5 hours off-site for a “team building” event is really a short amount of time. Many times these are weekend — or even week - long—activities taking place off-site. So I would not get too wrapped up in this being an imposition.