Originally Posted by ol240z

Salt or salty water and freezing temps cause the concrete surface to pit. I also store a car in the garage and don't want the salty water collecting under the car in storage (my garage floor wasn't properly sloped so water puddles in my garage). When you come into your garage at night, the snow and slush under the car and in the wheel wells drops off (usually the garage is a touch warmer than outside temp). When you pull out, you can use a squeegee, but it still leaves a salty residue. After awhile the salt actually starts to crystalize on the floor. If you use water and a squeegee to clean and squeegee the water out into your driveway you end up with a huge slab of ice. Using the snow to clean the mess allows you to sweep it up and toss it off to the side of the drive.

I would guess that is not a problem in Cali.