I don't think there's anything at all wrong about not wanting kids. At this point in my life all I want is a puppy
That soccor mom is a great example of people that I don't like. I mean, if she LOVES kids and has 15 of them, is the soccor mom, takes her kids to ballet practice, band practice, soccor practice, and still has time in her life for herself, her husband, and the PTA, good for her! She's getting what she wants in life, right? But there's nothing wrong with you or anyone else who doesn't want that life for themselves and that lady has no reason to get all defensive.
Personally for me, I think I may want kids eventually... but not at all anytime soon. No more than 2. I grew up in a family with 3 siblings and while it was crazy sometimes, it was a lot of fun growing up... and even now when I want to talk about something, but not really to my friends, I know I can always talk to my sisters or even my brother to get a guy's perspective
So that is the reason I would want 2 if I ever decided I really did want kids in the future.
If I had kids, I would definitely want them sometime within the next decade maybe... because personally, I wouldn't want to be like 70 when the kids are graduating kindergarten.