I have a hard time finding comfortable footwear. If I “watched my diet and exercised every day” I suppose my feet wouldn’t get so sore. But that’s the breaks.
I bought a pair of Keen Newport H2 sandals because they sported an enclosed toe. They looked like the perfect thing for canoeing and two weeks on the waterways of Algonquin Provincial Park proved it. I was concerned that they wouldn’t be heavy enough for walking long portages, but I was wrong, they were great on portages of a mile or more and my feet didn’t hurt at all. I could have left my heavy hiking boots at home.
Sandals are great canoeing shoes but most don’t protect your toes. The same open design that facilitates quick drainage when you’ve been walking in water also means that there is no protection from the cold (August in Canada can be cold!) so I brought a pair of neoprene socks from Campmor that kept me warm.