You could put your wallet away while the cashier is putting your cash in the drawer and getting your change out. However, if you’re at one of the longer lines that has the conveyor belt it’s unlikely you’d be holding up anyone behind you because they’re not likely to be ready to check out in the short period of time it would take to put your change away, and it’s not like putting your change away is going to stop the cashier from starting to scan the next person’s items.
You could put your wallet away while the cashier is putting your cash in the drawer and getting your change out. However, if you’re at one of the longer lines that has the conveyor belt it’s unlikely you’d be holding up anyone behind you because they’re not likely to be ready to check out in the short period of time it would take to put your change away, and it’s not like putting your change away is going to stop the cashier from starting to scan the next person’s items.