I just want to add that for me, daycare WAS unique in how much I took it so personally. As a server, I may judge, but I really don't care. I am an equal opportunity tip taker!
Everyone gets the same service and I make great money, but it is an experience that lasts less than hour in most cases.
As for daycare, I stopped regular daycare due to family stuff, but I do drop in care (a lot of my server friends have young kids). I help parents when they work and I am way more selective on kids. I like that I can control who I work with and I take raising kids very personal, so it is a really awesome experience when you have a great family who really cares. I also like that I can detach and take no kids when I am feeling disenchanted with parents.
So while I don't think venting or judgement is unique to daycare, maybe the reason for those sentiments is coming from a different, more personal, place. I give myself timeouts from it all, so I'm not sure what the answer is, but I just think it is tough to see so many kids struggling and so many adults just wandering around worried about themselves.