They look like they would work well in the large centers when they play with huge budgets but I think you would have to move a $#$% load of snow to make it cost effective.
Boy would there be a mess if you used a melter up here the last few days. You would literally freeze your assets down
They burn somewhere closer to 30-40 gals /hour they are VERY expensive ( about 1/4 mil and up). The small portable unit is about 8K /month to lease for the winter, but if you have a lot of snow to move, or no place to put it then they can be cost effective.
And regardless of the operating costs, you have to have a place for all the water to drain to. Cities with municipal storm drains might not have a problem, but where would all the water go in a large rural parking lot? Seems like you would make a big skateing rink.