In reply to mike kann: It's a very grey area (like soooo many things in Italy). I think the ski areas tend to adopt the approach of covering their arses by generally criminalising people skiing off piste, then turn a blind eye to most of it if there is no risk. But if you do set off an avalanche, or your chosen off piste is blatantly dangerous, then you're in deep poo & especially so if you haven't got transceiver, probe and shovel. Thus, squirrelling down the side of the runs is OK, but skiing an open slope which could trigger a slide onto the piste and it's a different story.
By way of illustration, there seems to be two levels of "Prohibition" generally in Italy:
"Vietato" is "Prohibited", which almost qualifies as just a general bit of advice!!
"Severemente Vietato" :"Extremely prohibited" which means they'll fry you if they catch you...
Traffic lights? Well, they're just a suggestion