Sometimes it makes no difference. I was on the toll road and handed the guy a $5 bill and my ticket for the $1.35 toll (decided I would just deal with all the change rather than confusing him by handing him a dime). He gave me back a five, 3 singles and bunch of change (mostly nickles). I drove off thinking I must have handed him the $10 I had instead of the $5 bill I had, but when I went to put the money in my wallet, the $5 was still there and all the nickels added up to 80 cents.
They all do eventually.