I'm going to put my dog's poop bags in other people's trash cans
Why would you put your dog's poop in other people's trash?
It's funny to see their reactions to my dog's poop.
Those garbage cans do not belong to you and thus should not be used to dispose of your own pet's waste. They paid for their trash cans to be emptied so it's not right to use their trash cans like that.
Whatever. I just love seeing them squirm when they open that lid and look inside the can.
How would you react if you found your neighbor's dog's poop in your trash can? This is inconsiderate of you to leave your dog's poop in their can. Treat other people the way you want to be treated.