I've always wondered why don't they allow the testing of those rockets in stable ground? We've done crazier tests, like nuclear testing: https://www.youtube.com/watch?v=LLCF7vPanrY
I thought the reason involved the FAA requiring SpaceX's to prove that the first stage could be guided accurately to the general pad area instead of plowing into a populated region. Landing on a barge out at sea reduces the risk of the latter.
Yep, a flyover of populated areas is avoided with an offshore lz/barge.