On another occasion we were at a bed-and-breakfast that served afternoon wine and cheese. The whole room (including us) was raving about how complex and delicately nuanced the white wine was. It turned out to be Gallo Rhine Wine in a box.
(BTW, it's absolutely not the case that all cheap wines taste good. We tried the notorious two-buck chuck and thought it was absolutely horrible.)
The point is: wine snobbery is bullshit. Find what you like and drink that, and don't pay attention to anything that anyone else says. If Beringer white zinfandel is what turns you one, more power to you. (Actually, the worst possible outcome for a real wine fan is to discover that they really do enjoy Romanee Conti or Screaming Eagle. I really like Opus 1, but I wish I didn't :-)
So I think this roll-your-own-wine blender is a terrific idea. I can't wait to try it. (I wish I'd thought of it!)