The TSA locks have widely circulated master keys because that's a basic requirement of the system–every airport has to have some to be able to open bags. I don't know anything about these OBD port locks, but I don't see any reason they'd have a master key, other than laziness on the part of the manufacturer.

Additionally, I'd imagine that such a tiny fraction of a percentage of cars have these kinds of locks that it'd barely be worth it for thieves to figure out how to bypass them, at least until there's more widespread adoption.