I think someone earlier made a good argument that no one really responded to.
Even if you only HAVE to shovel ‘cuz of the law, and not a previous moral obligation, its obvious that as a community we’re going to do something to make streets passable. Now the method is through law-enforced(?) private shoveling, like it or not. Today people are having a hard time because of you. Fits the bill for ‘Yashrus’ in my book.