How do YOU keep people from feeding your kids, your dogs or your cats?

I had 2 scary looking dogs before the current ones so I am not used to people doing ANYTHING they want to do to my dogs. We were just walking and a woman and a 3 year old girl approach from behind. The mother encourages the little girl walk up to my male dog and out of no where the kid has an Oreo in hand and he goes for it -- the chocolate cookie, her hand everything. 10 seconds earlier everything was fine but now my mind is going 'lawsuit if he knocks this kid down, lawsuit if he just bit her hand and what is wrong with this mother that she just pushes her kid toward any dog with food in her little hand ?!'

I shove my hand in his mouth and scrape out about 70% of the cookie before he can swallow it but I'm still worried he will get sick. We'll see. Meanwhile the mother just walks away like it was all nothing.

My other problem here was the meter readers carry dog treats. I never feed other people's kids or dogs but people try to do it all the time like it is the most normal thing in the world. They apologize to my dogs if they don't have something. The meter readers feed "treats" to everyone's dogs and they like for the dogs to get excited when they see them and run to them and jump up and all that risky stuff. It scares the shit of me that these guys are essentially training dogs to run at and jump up on people who look and smell like cops. That is a recipe for getting my dog shot or put down. Fortunately, I asked nice and they don't treat my dogs anymore.

This country kills 5 million dogs a year and many dogs wind up in shelters or put down by court orders because of "behavior problems." I am starting to understand better where these behavior problems come from: most people have no clue about how to train a dog and what NOT to feed them (grapes, onions, garlic, chicken bones, coffee, beer, caffeine, chocolate, raisins, wine, tobacco, pot, cat food, cat poop, macadamia nuts, avocados, spoiled food (!), mushrooms and uncooked dough (it expands)).

So that's my rant. Any tips?