1. When they leave there skies lying down on slopes instead of in racks

2. They are too loud when walking inside with there boots on

3. Middle aged men (or worse) with beer bellies in lycra racing suits

You forgot:

4. When they perform a "stand in the middle of a slope and look up the hill so people think they have friends that they're waiting on" and form a virtual blockade

5.When you arrive at the slope after a night of fresh snowfall only to see the beginners in their flying V snowplow scraping every last bit of powder off the sides expposing yesterdays packed ice.

As for not letting skiers or snowboarders on particular slopes I don't think so. I do think they should start clipping tickets from anyone if they go on black diamonds or steep blues and scrape off the snow because they can't make a real turn. There is nothing more annoying than that let me tell ya.

You also forgot:

6. When they carry the skis and the poles around people, watch out for pole tips or the ski tip as it may whack your body part or poke your face.

7. Watch out for those falling pole(s) from the lift chairs up above.

8. When they bomb the mountain and cut it to close to me riding over the back of my board and take me out they continue down the mountain like nothing happened. Ok this only happened once tome but it pissed me off

When they pull up beside a snowboarder on a narrow trail with slow moving traffic ahead. Without doing a jump-slide, it's vitually impossible for a snowboarder to slow down if they can't turn.