They used to refill them. The small ones were 2 cents I think, same as a postage stamp. The bigger bottles were 5 cents, same as a newspaper. Deposit bottles today should be much much higher, like .75 to a $1 to equal the old ones.
My friend Geno and I bought our first car a ’48 Chevy with $25 worth of soda bottles we got from relatives friends etc. Also, stores that sold soda had locked cages where the bottles were stored until pick up. Like Copper these days. Valuable enough to attract thieves.