Some online posts claim that Hostess bakeries on the West Coast still wrap them in foil, but I'm in Seattle, and I only ever see the plastic. Not that I'm a regular Ding Dong consumer these days, but I may have to undertake the research.
That first link, by the way, is via Waffle Whiffer, who has an awesome Web site and is officially a FOG (Friend O' GenXtinct). Also note Minnesota Twin great ROD CAREW on the box.
Waffle Whiffer also found Ding Dong shirts, featuring the long-since-deposed King Ding Dong, at Target!