Upset people because you DONT drink alcohol

Just to respond to some comments on here:

I was at a restaurant/sports bar to watch the Bucs game, not at a club and there was no dance floor. It was a restaurant with a bar, just like Bennigan's.
I was with a group of friends and people I just met, my friends didnt comment on my soda because they know I drink alcohol, it was the new people who inquired as soon as I said 'diet coke please'.
I do drink socially.
I have never thought myself to comment on whether someone drinks alcohol or not so I'm wondering why other people do.
I have noticed that it is the people who drink to excess that tend to comment.
I am 45 and the commenters are all ages so how old does one have to be before it stops?

Wow ok. Wow. I love how everyone on here who DOESN'T drink is saying "Oh, it's because they don't have self control and feel bad about themselves" or some other slightly insulting comment toward the drinkers. Having been both the drinker and the one not drinking, there's usually an obvious disparity between those drinking and those not. The sober person often seems uncomfortable or annoyed or even left out, and that makes the whole group a little uncomfortable and can put a bad tone on a good night. It has nothing to do with being judged for my lack of self-control; I certainly don't feel guilty or worthless for tipping a few back. I just don't like getting eyes rolled at me if I laugh a little too long at something. Sorry that I'm having fun.

Reasons why I may ask someone if they're sure they don't want a drink:
-Money can be tight in my friend group, and I'll pick up a drink or two for my friend if they actually want it
-If there's a specific reason why they're not drinking, they may want to talk about it but aren't sure how to bring it up (medical issue, etc.)
-They've obviously had a stressful day - one drink won't ruin a diet, but it will help you calm down a little

That said, if they've stated they're fine with soda or they're not drinking for whatever reasons, I don't pressure them. I certainly leave people who flat out don't drink alone. On nights where I choose not to drink, I find the pressure coming from people who just want to make sure I'm having a good time, like the host of the party or a friend who knows I've had a bad week. It's easy to deflect. Offering someone a drink and hoping they accept is similar to offering someone a homemade cupcake - you want to share an experience with them and want them to enjoy themselves.