A zone block affects everyone, friend or foe. The only problem with maneuvers is that then you need tags, and technically that means one "free tag" perhaps and then fate points should be invoked.. of course as a GM you could compel falls (offering fate points, that then require fate points to buy out of), which could indeed be very fun.
the problem with a block is that technically, one person breaking it should break it for all, which is kinda lame when the floor is iced. So tags might actually be better here.
(For the record, I don't consider this "arguing", just.. er... discussing?)