Re the guy with his 14 year old son getting abusive remarks. “Proud Dad” on the T shirt should do the trick. I recently saw a little child, about six, wandering around my condo lobby. In the otherwise deserted lobby a middle aged Belgian was peering at the bulletin board. All I asked was, “Is that your child?” because he was small and if unchaperoned I was going to call the guard to help little “wandering Billy” find his mom. The fellow became really ticked off at me. I was suggesting nothing about him or his habits, just natural concern for the safety of a little one. It works both ways, so take it in stride, and talk to your son about it so he understands what is happening and should not feel awkward. A fourteen year old today knows as much as most of us knew at seventeen “in the day.” You cannot protect him from what he should understand to protect himself when you are not on hand. Goodness, we had our first “stay away from the strange man offering candy in the park” movie when I was in grade school in the 1960s.
You have a good heart and looking at life sensibly. Your T-shirt should do the trick, otherwise ignore the people who are abusive.