But if I got on the bus and a man on there approached me and said this is a really nice bus and since you're riding on it, you should donate money.
I would say the bus is free for a reason and it clearly brings in revenue to flourish and continue operations. But if you, sir, would like to donate, feel free to do so. But don't corner other passengers and tell them to donate to the free bus just because you did. That's weird and obnoxious.
Best wishes to you bus donation vigilante man.