It is possible to buy from DM and use Click and Collect, meaning zero delivery charges (pick up from a store 2hrs after ordering online). If you pay on a WISH card you save 5%, and if you use Starthere (& it decides to work you save another 5.25%), so the DM price can be quite a bit lower.
Taittinger - $49.75 in any 6
Case Price $298.50
Less 5% ($14.93)
Less 5.25% ($15.61)
Optimal case price $267.90, about $50 cheaper than epiqure.
If SH screws you over, you are still only paying $283.58
FF earn depends how you buy the WISH cards. Assuming 1x - 283 points; 1.5x - 425 points; 2x -567 points; 3x -850 points
But yes, as always YMMV...
e.g. If you are sitting on an epiqure account, close to the 6k bonus points and near the end of your member year, then the equation changes somewhat.