I work in a small startup of 10 people in a house converted to an office that's spread across 3 floors. I am friendly with all coworkers including people from another startup that's sharing the space.
I love shopping for my needs online. E-commerce has tremendously improved to the point that there is nothing I'd have to step out for these days and find it all on Amazon. From t-shirts to my hamster's food to gifts for my parents - I order it all online and have it delivered to workplace because that's where I am there all through the week. Note that in Bangalore, you cannot schedule deliveries.
My coworkers who am friendly with often jibe at my deliveries. At first I tried to reason by telling what the package was and justifying how much I needed it. Then their constant jibes with every package is getting to my patience. How is it any of their business to question my buying habits or purchases?
Deliveries are picked up at the door by our office manager. It doesn't bother anyone in any other way. Then why do they bother me with questions? I'm starting to feel guilty and scared to spend my own money. I'm starting to feel harassed because every time I want to place an order I feel ashamed.
Edit: After reading all the answers, I am clarifying the following:
1. You should not shop on the company's time.
I shop on my own time. I simply schedule my deliveries to my workplace.
2. My boss's take:
My boss is OK with scheduling personal deliveries to workplace. He himself orders a lot of things online - but obviously nobody questions him. He doesn't make fun of me, and sometimes asks what I got. He often opens his own packages in front of everyone in order to show us what he got. The packages he doesn't open in front of us nobody bugs him about.
3. Meaning of "taking jibes" and "making fun":
The only other female co-worker I have is friendly with me (and vice versa) but she is not a online buyer, and hence finds it absurd that I do. Her constant commenting every time a package arrives is feeding a stereotype that I am a shopaholic, which the others have picked up on. I don't think it's anyone else's business to figure out whether I am a shopaholic or not.
4. Deliveries:
Another team is situated on the ground floor and it is they who receive packages by indicating the delivery man to leave it on the table. The office manager will then send an internal communication to allow her to receive and post (if any packages) through her as she thinks it saves us a trip.
5. Are they opening your packages?
No, they are not.
6. Are they making fun of the things you are buying, that you buy everything online, or that you have everything delivered to work?
They are making fun of my buying habits. Even though the Bangalore is known to be a hub for delivery startups, the idea of having of ordering so many things online is alien to a lot of people. Hence there is always some excitement when one receives package (which to me sounds a bit childish). Why should they get excited over someone else's package? Do they implicitly think it's some shiny toy that the person receiving will flaunt around?
7. Do I open these packages in front of others?
No, I take the box and keep it with me quietly. Yet, the fact that I received a box attracts attention.
UPDATE
After more than 3 years of leaving that workspace, I'd like to update that am still a very much an online shopper. At my current workplace, when I worked in a smaller team, I was still asked strange questions like "how much do you buy" and such. I moved to a bigger team now and don't get asked that as the trend of buying online is more prevalent among others too. But I also do not get any deliveries to office, I get them delivered to my home where I have a dedicated space for my deliveries and all the regular delivery folks know where to deliver my items.
Now, when people are being nosy about my shopping, I answer them with silence or at best a sly smile and continue doing my work. Ignoring people is an option that has worked for me.