Well, according to Family Guy, Twinkes can servive anything. That means that maybye they are from before WW2
I know we're joking - but in reality, Hostess products have surprisingly short shelf-lives. Twinkies, for instance, become dry and rock hard in a few years time. Like an old piece of cake, I guess.
Another tidbit is that the banana flavor has been brought back before - most recently as a tie-in to the recent King Kong remake. This one is far more fun, of course, because they've brought back the 1970's version of the mascot.