I'm surprised you do not already have a blog post cued up about this topic.

You be nice to people by respecting their response, if they do not respond to you or respond negatively; you leave them alone. Sure, say "hi" but if they don't respond or respond negatively, you leave them alone. This is very easy to understand.

I work with abused/abandoned/neglected children so maybe I'm just too sensitive to this but it is always a red flag when an adult male attempts to repeatedly interact with children that 1. they do not know 2. have already responded negatively or not at all. I mean think about it, those kids are forced to be at that bus stop every day. That is a space they have little to no choice but to go to, every day. Now this adult man on a bicycle is going to come by and cajole them into paying attention and responding to him. How often is he going to do this? Every day? Is he going see something he didn't like in the morning and then come back and wait to confront someone in the afternoon? It is creepy and is not behavior that is appropriate.

I assume your girlfriend is an adult and as such would be on equal footing should she decide she did not want to talk to you or interact with you in public. There is no societal expectation to defer to a adult peer in public. However, even though it is diminished significantly from days past, there is still a strong deference instilled in most children towards adults. Rights and respect of children is still such a new concept that it is hard for a lot of older adults to understand and oftentimes hard to accept once they do understand.

This was not meant to be offensive, it was meant to be educational. Sometimes knowing how to behave in public is not intuitive and it can be helpful to use the things one should not do to start a frame of reference.