So they've gone ahead with this anyway. Signed into law today and commencing on 11th January next year.
As well as the ban on earning or using loyalty points for alcohol, there's a ban on selling at a reduced price where multiple items are purchased. The 4-for-€10, 3-for-€9 etc seems to be the backbone of the craft beer trade at the moment, where volume is crucial for survival. Offies will now have to either stop it altogether or reduce prices across the board.
From my reading of it, the Galway Bay vouchers shouldn't be affected, but the ultimate decision there is with Galway Bay -- they might see it differently.