Most of the differences are going to be around keeping you warmer, and keeping the visor from fogging with breath shields, venting...
Helmets are also designed for specific types of uses though. If you are doing slow speed trials riding, then you want a lighter foam in the helmet, almost approaching bicycle specifics - because you want it to absord the impact instead of transferring it. As your speed increases, the type of impact it is protecting you from changes - and so does the helmet design. Pro-Tec uses the same shell in my kayaking helmet as it does it's snowboarding helmet - but the foam is harder in the snowboard helmet to handle a harder hit. I would think that a snowmobile helmet would be built for the same type (speed) of impact as what you would encounter on a maxi scooter - but each helmet model is different...
Readers Disgest Version -
I would think it would be a good helmet for cool weather riding, but may overheat on hot days...