When it comes down to it... the manufacturers just need to make a choice. Either get gray market outlets to abide by the same rules as they put on authorized dealers, or have no rules, or stop gray market shops from getting product. Pick one of those and go with it.
I am in a unique position in this industry as I've spent a lot of time talking to the presidents, owners, ceo's for many of the scuba companies. And some of them have admited that they have been lying to their reps and dealers for years, saying they don't know where the gray market sources get their gear...
And I've talked to reps and owners that have had meetings with LP and seen boxes of equipment coming in on trucks that were straight from manufactutrers that "Don't know where they get our product?!"
Be honest, if Atomic can stop them from getting gear, if Oceanic and Aeris can stop them, if Tusa can have them selling at the same MAP price other retailers have to deal with, then why can't scubapro, aqualung, etc? Because they choose not to.