How would the biomechanics even work for a 8-pound, quadrupedal animal... their legs don't even work the same, how would the boots work? They have a lot less hip mobility too. Animals can skateboard because they just have to lean and let their weight do the work, but proper skiing/snowboarding requires actually flexing the gear.
Maybe some ape or even a long-legged bird (bipedalism, hip mobility) could ski, but not a quadruped. Not in any normal and/or safe sense, anyways. How would bindings work? Can a cat even make short turns? Four little skis or two skis and four bindings? Not even considering training an animal to chill while strapped in to gear they can't bail out of