Does it really matter? At the height of my collecting i had over 160 moz/smiths vinyl and over 240cd's. Does that make me a bigger/better fan than anyone with just the quarry, ringleader and yor cd's? No it doesn't. It make's me poorer though:nopity:
Well, if they were "bandwagon jumpers" they'd have abandoned ship by now as his popularity has only declined since that career high. They'd have scuttled off and attached themselves to Razorlight or similar, just as hundreds of thousands of Manchester United fans will find themselves football orphans when the blessed day on which that club returns to where it belongs arrives.
Seriously though, if some people only own one Morrissey or Smiths album and have never gotten into the rest that's hardly worth condemnation. It's better than a big, fat zero.