****UPDATE**** Nintendo got back to us with the following official reason for the games' removal:
"From time to time, our software lineup changes for various reasons. There are currently over 350 classic Virtual Console titles available for purchase in Wii Shop Channel. We’re confident that consumers will find something they will enjoy."
Oh, various reasons! Glad that's cleared that up.***UPDATE ENDS***
Donkey Kong Country returns... to the ether next week, as all three classic SNES platformers will be pulled from the European Wii U Virtual Console. According to a news update on the console's online shopping page, you still have until the 25th of November to buy Donkey Kong Country, Donkey Kong Country 2: Diddy's Kong Quest and Donkey Kong 3: Dixie Kong's Double Trouble.
We have contacted Nintendo to ask why the titles are being removed and will update this story when we hear back. Presumaby a license has run out, or (more excitingly) there's an HD collection heading to Wii U that they want everyone to buy instead of the cheapy Virtual Console versions. Stranger things have happened.
Don't forget, all your Wii Ware and Virtual Console titles are playable on Wii U, so if you can imagine a point in time where you'd want to play one of these SNES classics on your shiny new machine, you'd better get downloading these pronto. However, they are limited to being played on the TV screen (at present) and with old Wii control peripherals, so don't sell your old Classic Controller just yet.
Source: Go Nintendo