I'm sorry this is so off topic but I'm going to take the contrary position. I had been left out of an aunt's wedding (age 4-prime flower girl age!) and so when I got married I made sure to invite all children, had 4 flower girls, etc. Well...my (then) SIL brought her 8 month old infant who had recently been ill with a virus. I was violently ill the day after my wedding, as was my maid of honor, and flights/trips, etc were cancelled. The B&B where we held the wedding had to close (the owners got ill as well) and we had to pay extra for that. It was kind of a nightmare. Ex-SIL still swears it wasn't her child. Nineteen years later I still shudder at the memory and photos of ex nephew makes me green.
After that experience I am much more sympathetic to allowing people to invite whom they want for whatever reason they want. It's their day, after all.
My thought is - you get to invite who you want. However, if you don't want to invite children (fine), you aren't allowed to get huffy/mad if people decide not to attend because they don't want to/can't leave their children. Equally, you don't have to accept any/all invitations that you get, however, you don't get to call people names because of who they have on their invitation list.
Having said that - I'm the person hanging out at the kids table!