While not exceptionally common, there are places and areas in
which things would be *very* broken if you could move through and
pillage them while as a ghost. Many of these may have sections
where you have to get through a hard section, but then once past,
there's relatively little danger.

Yes, if we *really* wanted to, we could probably "fix" these with
time and patience, but often the only way to realize something got
missed is when you notice character X exploiting the bejeesus out
of something that was poorly designed.

As to looting your own corpse...meh, with gear decaying right back
to you, it's barely a concern. If my stuff is somewhere I'm
waiting for decay, I'll just run around collecting easy things I
might need until gear comes back. If it were back in the day
where we're talking hoping to pit loot faster than the guy
standing next to me? I'd be more on board.

Also, there *IS* that disclaimer that no-one reads...

Be careful, for even a ghost should fear some dangers!