I think the biggest complaint people have about lack of manners is for those kids that tend to push and shove their way to the front of queues, knock little ones over without saying sorry, snatch things when offered and don't ever say please and thank you.
I don't judge kids based on the please/thank you thing alone, but it's a good indicator of how a child will interact with me or my family. And I do get a bit judgey pants if a child is unpleasant, pushy and doesn't say please and thank you.
Manners are a big thing and I'm not even vaguely embarrassed about making a big deal of it in my house. It's part of a bigger agenda that's called respect for others. And when I say I bully my child into, I mean that she has had it drummed into her from a very early age that she has to consider others...not before herself, necessarily, though there are times when others should come first like if they're smaller or if they're guests in our house. Is that not just common sense?
There are some things we have to teach our kids that aren't easy for them to take on board. Saying please and thank you is the least of them, but it's a foundation for other skills like respecting their teachers, complying with rules, being fair. To some people these are not just things you choose to do, they're the very corner stone of civilisation. Hence the expression that people are being civil, I guess?
I want my child to be socially adept, to be integrated easily into school and work, to be a likeable person. If I lay the law down on that am I really wrong???
I think the evidence of my lovely 8 year old dd, who I'd be proud to take anywhere and who is a delight to old ladies across the land, proves that I'm not