Further stonerware TM puzzles

The site mentioned in the previous entry also sells beer can covers that imitate soda cans. Presumably the use is to smuggle beer into venues whose rules prohibit alcohol but allow soda. The covers themselves make a gesture at parody -- Dr. Papper, 7 OP, and Diet Pipsi -- but the ad copy uses the conventional spellings. The misspelling might be enough to dispel point of purchase confusion, and perhaps even confusion over licensing, but what about post-sale confusion?

The problem for the trademark owner is that the usual harms from post-sale confusion seem unlikely, since only if an observer notices a difference from regular cans is she likely to pay any attention at all. I suppose it's possible that someone might grab a friend's "Dr. Papper" and end up with a mouthful of beer, but the chances she'd blame Pepsi for that, instead of the jerk who snuck a beer into a beer-free place, seem extremely low. What this reminds me of is the practice of filling actors' beers with nonalcoholic drinks so they don't get drunk over multiple takes, which is an unobjectionable use of a branded product even if it falsely suggests the contents of the beverage.