This is another example of how parents these days think that children belong wherever the hell they want to take them. How are kids supposed to learn any kind of manners, appropriateness, consideration of others, etc. when they are dragged to all kinds of places they shouldn't be and then they are allowed to run around, screaming, making a fuss, getting others sick and getting snot everywhere?
Yes, parenting is hard. And it means if your kid is sick you have to stay home and figure it out. Kids don't belong in study areas, at rock concerts, at R rated movies, etc. My mom even gets disgusted seeing this kind of thing, and says when she took care of us she just had to stay home if we acted up, even if she took us to the grocery store and we had a fit, we just had to leave so we wouldn't disturb others--and then we were taught about appropriate behavior when we got home

People sign up for these complications to their daily life when they have kids, but those of us who don't, or don't bring our kids to these places, shouldn't have to suffer along with them!