I've even found small pieces of furniture in perfect condition on weekend walks around my neighborhood. I've brought items home such as: a barely used small bookshelf, a wooden chair and a nice large basket. I've even seen larger furniture items like bed frames that I simply didn't need, but were in great condition. I always clean and disinfect everything I bring in the house, but I have absolutely no problem with taking people's stuff they no longer want off their hands! The stuff I've seen people throw away is usually not junk and I'm sure they know when they leave it on the sidewalk that someone will take it before the trash people come to take the unwanted items away. It's also environmentally friendly to encourage reuse of books and furniture items.
On Sunday morning, I decided to leave my own box of books I know I'll never read again (mostly mysteries and romance novels), and they were all taken by the end of the day. It's my small way of returning the favor and encouraging my neighbors to keep the goodwill of book and furniture swapping going.