Quite simply, because it has character. The same reason why people buy old rusty hulks of 80's BL. They also happen to be good offroad with a very short wheelbase, and, if you live in russia, very good spares availability.
I had one years ago when I worked catering up north. Purple with shell suit graphics! Awesome. The doors didn't lock though and some knob stole my drivers seat "for a laff" never saw it again.