I eat it all, too. Most J-pouchers have pretty varied diets. Some do notice trouble foods (and some of these are probably deceptive or echoes: I still avoid a glass of milk even though I finally discovered I was fine with it). Others do have lots of food sensitivities. If you don't know which category you are in then it's best to pay attention and figure it out. And for most of us, the best advice is to not overeat. The corn will come out looking like...corn, but that's just fine.
Remember that millions of people with healthy colons complain about their digestion all the time.