You said that an Haiti airport "porter" might be offended if he's called a "bouretye", but isn't a "bouretye" a "porter"?

Yes.
A bouretye is a porter, but a porter is not a bouretye.  Well, I should rather say, not everyone who works as a porter in Haiti would consider themselves a bouretye. 
Does that make a bouretye a bad thing? No.  But some people do consider it a lowly job.
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