And then what do you do with the coins, hope that one day you'll get the chance to use them?
You dump the coins in a change jar on top of your dresser. Then once a year or so, when you have accumulated $100 in coins, you bring the jar to a coinstar machine at your local supermarket and get the coins converted to an Amazon gift certificate.
I have an algorithm for minimizing my coin count. When I buy a soda or snack from a machine, I put the smallest denomination coins in first (nickles) and then work my way up (dimes, then quarters) until I have put enough money in to make my purchase. The machine gives me change, and as long as the item costs at least 25 cents (a practical certainty!), I'm sure to have fewer coins in my pocket afterwards.