As with most jobs, knowing someone helps.  If you work at a ski shop for a few years, you will start to get to know the reps and its not that difficult to get some type of rep job.  A marketing degree or some type of other rep experience (drug, pepsi, anything)would help, but is not needed.  From what I have herd, there are perks, but you travel A LOT and pretty much live out of a suitcase for part of the year.  It's not for everybody, but you may like it.
There are also smaller reps that rep for small companies that might just go to a few shops.  Anyways, good luck.