Yes, typically called a bonding agent. It's a good idea when adding new concrete to old.

I'm sure there are but I don't live in a county that has enacted those rules. My county only says you have to have a nozzle on the hose so as to not have the water running down the drain the entire time you wash your car. Seems like a pretty fair rule to me.

The mindset of I can use all the water I want as long as I pay for it is fairly shortsighted in my opinion. Especially in a location with such bad drought issues. There were/are municipalities that nearly are out of water for drinking. To "waste" it to keep your car clean because you paid for it would be a dick move in my opinion.

We're all still in one, just not in the "exceptional" category, only "severe" or "moderate" now.

Lots of places have bans on washing cars in the driveway. I'm guessing OP just doesn't want to take his car to a professional car wash place.