Why didn't you go over and wake them up and ask them?

Seriously...maybe they got robbed and couldn't pay for their room and were waiting for funding.... I doubt the hotel was just letting homeless people sleep in their lobby. I would hope they would let the homeless people stay in the empty rooms instead It's weirder to me that you are pushing them for an explanation - seems you already got one and its MYOB, you just don't like it.