I think a lot of it depends on how you have been brought up, my mum would have gone mad if we were rude to anyone especially if it was an adult. A lot of youngsters dont respect their elders nowadays
I find that alot of rude people tend to be elderly. If i was shopping & caught them with my trolley i would be expected to say sorry ( which i would) but when they do it to me & usually take half my ankle with them they don't need to apologise because they are elderly. They say about youngsters being rude, but they aren't the best role models really are they. I agree we should have respect for our elders but its a two way street