Not a lawyer. By the letter of the law, yes.
They had to jump the fence - presumably the gate was secured - in order to get to the house. Further, they walked around the property looking for the owner. This looks to anyone without more knowledge, very much like trespassing.
Just my 2 cents, I’m not trying to defend or accuse anyone.
Except in Germany. Anything put outside for refuse collection is considered property of the town or city.
Taking something from the pile is punished as theft, and if caught, you will be fined.