The ol' folks from the 80's and 90's grew up with official and pirate carts so I see why he'd prefer to buy 50-in-1 carts over a flashcart, for nostalgia mostly.
I suppose there are those people, but this guy was not that. I don't think he wanted to be bothered with searching and downloading files and the associated risks. There is also a degree of plausible deniability. "I didn't know the seller hadn't paid his licensing fees."
All this also takes having some technical skills or the time and desire to learn what you don't know. Most people are not going to go through all of this. None of the tools are are exactly dummy proof and take a certain degree of maintenance. I haven't messed with the Wii in about 3 years and it probably could use some updating. The boys have mostly been into the 3DS, Minecraft/Terraria on PC, and spend 90% of their gaming time on our handed down iPhones.
In three years of iPhone/iPad gaming the two of them have spent less than the cost of two Wii U games on the App Store. That is a major problem for the big 3 console makers.