Our bins were collected last Thursday.
Some houses regularly leave their bins in the street or back alley.
If my dog has inconveniently shat, I'll use these bins to dump the poo if I pass them.
My take on this is that if people were bothered about random strangers using their bins, they'd take them in like everyone else does and like you're supposed to. If there's a bin hanging around on the around the street I'm going to assume its for public use 
My neighbour (who does collect his bins in like me) was shocked at my blatant use of other people's bins. I think I've gone down in his estimations and, TBH, I wasn't very high up in the first place 
Now, clearly the unreasonable people in all of this are the lazy cunts who can't be bothered fetching their bins in. But, aside from them, if we start from the assumption that these lazy fuckers will always keep their bins out... AIBU?