There's tons of Mazda domains online that aren't owned by Mazda. Mazda forums, used Mazdas, Mazda enthusiasts, etc. etc. Now that doesn't mean you're going to get much if anything for those domains, but just because Mazda is in the name doesn't mean they are coming after you for TM violations.
I'd say reg fees most likely across the board, but there's a tiny chance you might get to high XX or low XXX on some of the Mazda ones.
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