When I first saw this I wondered why more drink manufacturers weren't doing this type of open-top can. Maybe it costs significantly more to produce? Either way the folks at Sly Fox Brewing Company have quite a differentiator here with their Helles Golden Lager which opens the entire top of the can.
Sly Fox's head brewer Brian O'Reilly says the open top beer can "allows the full flavor and aroma of the beer to hit the drinker's senses." Makes sense to me. If nothing else, chugging the beer should be easier.