from the skier's perspective it is a load of shit. but if you or your bud were to get hurt in the closed run, even if there was a rope or big signs saying trail closed or whatever, you could sue the living fuck out of the resort. so most resorts take that shit super seriously to avoid ridiculous lawsuits
but i agree with this bullshitness. if i wanna ski some pow, you better believe im jumping a rope to get there