Did people forget how to behave?

Rhetorical question - but I was baffled at some of this I encountered on my last trip.

1) Two people having a side by side ‘normal’ conversation at a volume and tone that made you expect them to start fighting

2) A man eating a sandwich out of the pack like a pig eating out of a trough. No hands, face shoved into the box

3) Eight, yes eight people deliberately taking a different seat than allocated. That was just in my section

4) Changing a nappy on the seat