I think they have gotten into the habit of trying to take them off, but who knows.
What I do know is that it's best to take them all off cause my 1990 rg550 had like a brownish white glue residue on it from the plastic aging and melting into the cavity cover on the back over the years.
Your 550 probably had brown paper protective on it which wears into looking like crappy anything, which doesn't come off.
It's kinda hit and miss, I don't remember when I see it or not, Indo definitely still has plastic, Fujigen mostly doesn't except the trem cover, if I remember right. I've got 15 to check in, I'll know for sure after :lol: