Companies will go out of business, restructure, and foreign competitors will enter the market. or increase their penetration. The size of the snack food and fast food sector may shrink, but the sector as a whole is not going anywhere soon.
Just be prepared for a massive push by Grupo Bimbo to capture Hostess' market share with its Marinela lines. If Bimbo Bakeries USA is smart they will buy the right to Hostess brand names and ditch Marinela in the US. They already have the factories and distribution networks and would only need to change packaging as they already make all of the same products as Hostess.
Hmm. Time to see if I can buy Grupo Bimbo stock.