The problem with pennies is that it takes an awful lot of them to be worth much and the bulk of all those pennies makes them extremely inconvenient to carry around. As a result of their lack of value and their size and weight, people tend to just throw any pennies they get as the result of a transaction involving change into some kind of a container. It might be a jar, bucket, bottle, or perhaps an ashtray, but one way or the other pennies tend to accumulate in this manner and as a result they go out of circulation. The apparent contradiction regarding this state of affairs is that the total value of all the pennies that are currently out of circulation would be in the millions of dollars and yet there is no way for any one person to capitalize on this highly distributed reserve of monetary value. Oddly enough, the cost of rounding up all those pennies would likely be almost as great as their total value.