Are you hoping to expand your Wii library on the Wii U by purchasing WiiWare and Virtual Console releases through the Wii Mode? You won't receive reward points for doing so.
The original Wii allows owners to link a single Club Nintendo account to register games, like Virtual Console releases, to receive surveys to fill in and coins for rewards.
This is still available to older Wii owners, but players running the virtual "Wii Mode" on the Wii U will not receive these extra incentives for downloading Wii software on their newer console - despite accessing the same catalogue.
Nintendo's reasoning for the bizzare move is due to "system constraints" - perhaps they quite simply, forgot?
Due to certain system constraints, Club Nintendo accounts cannot be linked to the Wii Shop on the Wii U. Games downloaded through the Wii Shop on the Wii U (in Wii mode) do not qualify for surveys or Coins.