"devotee": an ardent follower, supporter, or enthusiast (as of a religion, art form, or sport). I'm not familiar with "devotee" used in the manner you suggest, Andrei. Re: "All visitors to Mecca are by definition pilgrims" I don't think the truck driver who brings in the gas for gas stations in Mecca would be a pilgrim, but he could easily be thought of as a visitor.
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