I have a 5 basses and another on the way plus 3 upright basses and an EUB, clearly that's far too much for one guy to play but it's a hobby and I suppose some basses will never really lose their value so it's money in the bank in a way.
Ironically when I was playing on a regular basis in the 80s and 90s I only had one bass, the EB Stingray and I could easily get away with having just that now but since I rarely got to the pub, or go out partying, have stopped riding motorbike and am not really into cars or anything else I don't think it's really a bad thing. Horse for courses and all that.