Apparently scavenging from kerbside pickup here is illegal, though I've never heard of anyone being prosecuted over it.
Observations from our last one... (the joys of working mostly from home)
A ute (pickup) with two couples and three lounges on the back, stopped across the road and studied the lounge on the footpath, lots of discussion, then unloaded one of theirs off the ute and loaded the one from the footpath - they were shopping!
Also a bloke with a trailer full of odd assorted BBQs and another with assorted white goods collecting.
There was a story about a couple moving house (not during the kerbside pickup), started stacking their gear on the footpath in anticipation of the removal truck arriving, only to come out and find some of it missing. It seems anything on the footpath is fair game.
Then on the other hand, my sister had an old table and chairs she put on the footpath with a "Free - giveaway" sign on it. Sat there for a week until one of her friends told her to put a price on it for sale. It disappeared that morning.