I'll bite: Honestly, nobody in Western society (except your mother, unless you're married to some sort of nobility) cares whether you're having kids or not. I certainly don't, my wife doesn't, nobody in my family cares...we've friends, aunts, uncles, cousins who didn't have children, either. But we chose to, and there's no going back. Believe it or not, we parents have our own major issues to deal with rather than badger others into increasing the population of this planet...neither is right nor wrong, and there's nothing wrong with either one. If you meet people like that, they're either desperate to sell or offload children's clothing, baby supplies, and toys, or they're doing it wrong.
I think people create their own self-manifested pressure in this scenario; while it's true you're friends might have them, and that changes the friendship dynamic (they have to spend more time with raising a child than hang out in the evenings), that pressure isn't exerted on you. Unless you're part of some fundamentalist-leaning family, nobody really wants to pay for more kids in terms of their time and money...but you also have to understand that it's well and truly Not About The Money.
What most parents don't like is when the non-child-rearing populace (some of whom who can't tie their own shoes with out instructions) is quick to point out how we should handle every scenario when you've never walked an inch in those very shoes. Believe me, there's no instruction manual for every parental situation, there's no way to always have a "back-up plan for the back-up plan", so don't try to Monday-Morning Armchair Parent when nobody asked for said opinion and you're not willing to budge an inch.
There's always going to be babies that scream in movie theaters, because there's selfish parents who shouldn't have done that in the first place. Or parents who won't escort their kid outside the restaurant after the first five minutes of a tantrum. Or times which are pretty much unsuitable for infants and toddlers (really, a 10:00pm historic walking tour?!?). Yeah, we hate that too...even more so than you could imagine, because we can be thoughtful to avoid much of that chaos in the first place; arranging our extra time to make sure others aren't inconvenienced during the spare times seems a double-waste when that kind of thing happens! There's always going to be parenting gaffes, just as nobody here has never dinged a car, right? Never said a word they'd like to take back? Bought the wrong damn thing? Same thing.
But keep your thoughts to yourself when you're upset that a kid is loud at mid-day in a city park, supermarket, airplane, bus...do you really think your noisy rabble is actually more important than anyone else? People do have to get out of the house. Babies can't always express themselves, and if you think a slap or pound is going suddenly make them quiet, then you have no clue what sound levels escalate into afterwards. Every child is a bit different than the next, and what works for one, doesn't work for another. On the other hand, you get a bit of empathy when these child rages occur: 1) That stinks, I remember that 2) Sure glad it's not my kid.
We get it, and we don't expect you to dispose of a diaper, change a baby, entertain the youngling, keep it quiet, fill a bottle, and hold it constantly. Have you been asked to a few times at large family gatherings...naturally, but compare a 5-10 minute session with 18-21 years of that. And later on, you'll be glad someone took the photo of you holding your cousin's baby.
Guess what? That was you. Let one's opinions Grow Up already.
That said, it's kind of amazing being a parent, but it also means shelving other things in life...not as much as you think, although a bit more so in the first 2-3 years. Sure, video games were the first to do, because real life became much more interesting and rich than somebody else's button-pushing vision. I don't really miss them. They grow up, too and they want to do the same things you do. You get to be their teacher, and you learn a lot about what you know (and don't know). Parenting is an Important Thing to Do, but that's not to say that there's not plenty to get out of life if you never had kids at all.