I have often left a bag for a couple of weeks at a hotel, sometimes it's my pillow and blanket and my flying clothes that I don't want to haul all over wherever I'm headed next.

Leaving valuables, it depends on the country and the hotel. I'd not blink about leaving it in Japan anywhere. And despite cultural stereotypes, I left (accidentally) a camera in an historic site in Cairo, remembered it about half an hour later. The tourist police had it.