going too far?

twice this week i've been in situations where i felt that i should give two strangers some personal advice:
1. excuse me sir, you have a "bat in the cave."
2. excuse me ma'am, you might want to think about getting that mole on your back checked out.

i should have at least helped out the guy in situation #1. when i was in college, i once walked around for an extended period of time with the skirt of my dress tucked under my backpack, exposing my behind (fortunately, i was wearing tights). to this day, i appreciate the kind woman who informed me about the problem. oh well. maybe next time...