Can can

Why don't they can rice?  They can corn.  Why don't they sell corn as
dried kernels that you cook up in water, like rice?  

Now several people will google and show me both canned rice and dried
corn, but that doesn't mean that those forms are popular.  They sell
frozen corn, too, and very recently they've really started to ramp up
selling frozen rice, but that didn't used to be common. 

And oats.  They don't can oats, either.  Steel-cut oats take at least
half an hour to cook.  Doesn't it seem like there'd be a market for
canned oats?  

-- 
Dover