It's possible that there could be some viable use case for canned mayo. However, for the life of me I can't think of a reason to not only microwave the mayo, but the entire container at once.
Mayo is a lot more versatile than people think, makes a lot of sense if you think about it, but you can use mayo in place of eggs in a lot of recipes. Fried mayo is something you should probably never eat, but it can also be pretty great.
This made me curious, I'm going to see if our supplier has #10 cans of mayo tomorrow while I'm at work. The mayo we get is in plastic jugs, and we generally wouldn't need that much at once, I just want to know if it is something that is made.
I don't think you'll find it. Mayonnaise has a mechanism of lipid oxidation catalysed by iron ions present in egg yolks. Most mass produced mayonnaise contains EDTA to chelate metal ions and slow down lipid peroxidation. Lipid oxidation is also known as rancidity.
You can test this yourself by leaving a metal utensil in some mayo for a couple hours. It should turn black from a redox reaction
Don't cans use a coating on the inside to prevent contact between the contained material and the metal of the can itself? Like tomato products are pretty acidic and would also react with metals they come in contact with but are a common canned good. Same with soda pop.