Why so few Murphy beds ?

generaly most rv ceilings are not tall enough for a north sought murphy bed, so that leavs you with a east west so one side of the bed is inaccessable with out crawling over your partner. Most people dont want this and they want a bedroom they can just close away and not have to make up to use the table or the couch and so on. I know I bought a bunkhouse that has its own room so the kids can sleep or what ever while I am in the kitchen doing stuff.

Steve