Ok, sorry to hog the podium, but here's one for Backcountry.
Backcountry, you're comparison of abuse in the backcountry neglects to detail the abuse of your engines and tread on the environment compared to that of a climber. The un (or lightly) muffled engines and the tread of the snowmobiles harm the wildlife (with noise and exhaust), the soil (with the tread and compacting of soil - recently mentioned in the clearing of the North Cascades Highway if you check their site), and the plants and trees (with the exhaust and the tread running over downed brush). You cannot compare this with a bolt or a sling.
As far as your Snowpark infringements, a climber or skiier pays (in theory) for the same Snowpark pass that a snowmobiler with a motorhome, or SUV (always with a large trailer attached) that you do. If you feel that you need more than one parking spot for a fifty dollar fee (required in several or our local snowparks), than perhaps you should plan on buying an additional pass. You take up more room in the parking areas, and (my bad if I'm incorrect) you aren't paying any additional fees or licenses to drive your machines in the backcountry. It was interesting in the related story about the jet ski vs kayak incident earlier. If that sh*& went down with a snowmobile here, there are no licenses or other identifying marks on snowmobiles to identify those who commit the infractions. A victim of such an offense would be pretty much S.O.L.
Vegetablebelay doesn't like the snowmobile lobby.