Yea i definitely still play Kelly's Pro and Transworld Surf (PS2) still and they are still fun, especially when its flat.
And surfing video games are NOT a bad thing. I can recall recall when I got those two games (used for pretty cheap, like $6-7 each). It was a rough time for me when I was still stuck inland, wavesick, and dying to be in the water. I definitely enjoyed a whole winter playing those games for hours in my basement, drinking, and ripping unrealistic but BADASS manouvers.
Made me feel better about not being able to get wet for looong periods of time.
Is it possible? 100%. Anyone remember going into arcades and playing the snowboarding games where they have the board and you lean to turn it? Its the same idea, just the user would have to buy it themselves.
Then you ask is it profitable? Guitar hero, Rock Band, Dance Dance Revolution, Wii Fit... These are all pretty profitable, but if it combined more than just surfing it'd be 100% profit. Say surfing, snowboarding and skateboarding.