I didn't look into the detail logistics (it's not my thing, I'm a cyclist and don't want winter in the middle of MY summer!)
I'm just going by the price differential between south america and europe in winter. Flight to Europe in summer cost a fortune compare to winter flight cost!!! That's going to jack up the cost of "summer skiing in europe" by a big handy chunk!
So, why bother with 6-9 hrs of jet lag to ski at some glacier for a few hours in the morning, when you can ski all day in winter condition, when the cost are similar anyway? More over, the scenery of the Andes are just as dramatic as the Alps (some would say the Andes are even more beautiful)
I went to pick up my buddy at the airport when he came back from Chile. As he picked up his snowboard from the luggage belt, we got a lot of amusing looks!