I don't re-use bags. They cost about one penny per pizza.
Re: raw in dough trays
If I was in the U.S. and a typical American high volume shop, then yes, raw in dough trays is faster. You probably sell more in one day than I sell in a week, but my price is probably 4-5 times higher.
The bags are more sanitary and there is no chance of the dough balls drying out. The bags in dough trays works for my dough formula, desired dough consistency, and workflow. I've tried most every method and this works for my business. I freeze balls for a few days and move to reefer for cold ferment on a schedule based on my historical demand each week.
I think the bag method is easy for the home/hobby pizza maker, which is what I gathered the original poster is.