@sleepinglion,
A lot will depend on how popular the virtual console was on the Wii, and did it’s sales continue on the Wii U or was it in fact all that big of a seller in the first place, my guess is it’s sales had got to a point where Nintendo decided to retire it then offer their retro games in different ways. And at the time I remember many on here and other gaming sites complaining about the service, price of games etc.
As for Nintendo clamping down on emulation and ROM sites it’s simply a question of copyright and legality, and all the arguments and justification in the world can’t excuse this, for example I could try the cost rationale to many arguments, for example if I feel an I Pad is too expensive, could I justify stealing one.
Retro items in any field can be expensive, this is usually down to the fact they are not produced anymore and are limited, this is before the auction sites and graders do their bit to inflate certain prices etc, you can’t blame Nintendo for not making things available forever.