Well, I haven't eaten it, but... it's... a can. A red can with white letters on it. A lot less unique than a souvenir cup. So if you think a red can is worth $5 extra bucks then I guess go for it.
Agreed although in fairness it looks like the can is actually plastic and smooth rather than jagged. So, it's not like they are selling the exact thing you can get for $.50 at the grocery store. It's basically a cup made to look like a can. Whether or not that's worth $5 and a smaller portion of food to you is up to you. For me, it's not.
I have read reactions from people who have sampled the Who Hash. The general consensus seems to be that it is a decent, perhaps even good, corned beef hash. Since you're primarily interested in the food, I would get something else unless you just really love corned beef.