But a can with optimal shape could be produced that contains the same volume of tuna. I think "tradition" is the factor here. Everyone knows that a can of tuna is like a hockey puck shape. If you all of a sudden changed it to a different shape, I'm sure people wouldn't even recognize it.
Most cans of tuna here (Uruguay) are not hockey-puck shaped - and soup doesn't come in cans either, but in Tetra-Paks, except for the rare Campbell's import.
Searching for images I came across this very relevant article on irregular can types:
When I look for tuna at the grocery store, I looked for the can shape, rather than the tuna section or tuna labels. If tomorrow I went to the grocery store, and all the cans of tuna were a different shape (or a different package) I would end up having to ask someone.
