if someone does something outside of what they know or feel is OK, no matter who that person is, it's time to detach/run/find another adult/tell us/etc., because that's not a good person.
As kids get older, it may be useful to switch to "that's not a safe
And that "safe" means not just "they might hurt you" but can also mean, "you can't trust them to behave sensibly, or with consideration for you, or the way other people do."
So someone who pushes boundaries but doesn't seem truly "bad" might still be the person who will ask to borrow their stereo and never give it back, etc.
That's the less-dramatic extension of the idea that "Good people respect kids' boundaries and don't want to make them uncomfortable."
I often boost kids up to get stuff, and I've offered food to kids who are in my vicinity when I'm dealing with food. I think I succeed at it because I behave in a way that makes it VERY clear--to kid and to parent--that I am respecting the kid's boundaries. I offer--and often I offer a choice ("should I hand you a lemon, or would you like a boost so you can get it yourself?" or "would you like a boost to the water fountain?"), I'm friendly but reserved, I wait for a response. before any option, I make it clear that I'm acknowledging a parent and incorporating their response.
Learning about boundaries, and respect, start really early, and the protective instincts you have trained into you in a method like GlassHalfFull's have applications that are not about literal safety or the traditional definitions of "bad."
People who make kids uncomfortable (people who make GROWNUPS uncomfortable) are people who cannot respect boundaries, and one should -always- regard them warily.