Interesting story - but I heard a different one (from the buyer at Desert Diamond).

1st part is the same, but they changed the name not because of Trop's card, but that there was a strip club nearby called "Diamond Club" and they didn't want any affiliation with that type of establishment!

Since I've never been to a place like that (hey, is that thunder I heard?), I can't confirm the story - maybe someone in the area can?