I have been a skier since the age of 7. Although I would never snowboard, it's certainly unreasonable to think boarders should somehow be banned from all ski resorts. However, I will admit that I find snowboarders to be pretty annoying and burdensome to the mountain and I have no issue with certain mountains claiming exclusivity for skiers only. Let me explain.
There is an enormously disproportionate number of shitty, beginner/ first time snowboarders on the mountain at any given point in time. This is because tons of idiots tag along with ski trips taken by groups of seasoned riders and have this delusion that they are gonna learn how to snowboard overnight or just want to be included.They clog up the mountain, getting in everyone's way. On top of that, these first timers will slide down the mountain with their snowboard scraping along the surface, perpendicular to the mountain, causing the nice fluffy powder to be scraped off the top layer. This packs the snow down and exposes the ice. This makes for a shitty surface until the groomers come out.I'm all for learning how to ski or snowboard. I was a beginner once too. But for whatever reason there are way too many of these pain-in-the-ass riders out on the mountain at all times. They also like to bypass the "bunny-slopes" and go straight to the main slopes that they have no business being anywhere near. This is likely for the childish reason that they are simply named "bunny". They end up falling down every 2 feet, right in the center of the trail, posing as a huge danger to other riders flying down the hill at great speed.So Alta Mountain. You are well within your right.