I wish more was done about people putting feet on seats too, but we all know that when TOCs have clamped down on it they're instantly accused of being over the top, too heavy handed, unfair etc.
Only yesterday coming back from Windsor, I had to push through someone with his feet up on the seat. He was a tourist, and apologised and said I could sit there as he put his feet down. But I sat on the middle seat and said 'No thanks, you had your feet on there and got it dirty' which shut him up for the rest of the journey. Mind you, he put his feet back up immediately after.
And on the trip into London, two people who had been smoking behind the kiosk at Hatfield got on and also put their feet up - and one promptly peeled the 'feet off seats' sticker and got comfy.
Management need to wake up and realise one day that you have to enforce the rules. You'll delay trains and cause hardship, sure, but only for so long until the message sinks in that it's not acceptable. But you do also need to shift this new belief from the general public that if a service was delayed, it's down to the person who is causing the problem or breaking the law, NOT a jobsworth that should surely find something better to do (like turn a blind eye to anything and everything).