That assumes the buildings can handle them. A company I used to work for was planning to put solar on pretty much all of their buildings. Until they found out most of their buildings couldn’t handle the weight without significant (expensive) reinforcing. Many of their installations ended up on the ground instead.
We have a rabbit and a cat. The cat has been with us longer. Whenever I’m petting the rabbit, the cat comes up and wants to be pet too. And only with the hand I’m already petting the rabbit with. If I try to use my free hand, he’ll ignore it and head bump the hand petting the rabbit.