Our parks been hammered year round since the '70's. In 8 years I only found 4 silver dimes. Luckily they wont ever quit wearing jewelry. Women have to wear it and most want their husbands wearing that ring too. I know one of my friends wives is paranoid. That's why he lost 5 wedding bands surfing.
I do know the parks I used to find tons of quarters at don't replenish. Too easy to hand a card. The beach though you still carry some cash. Only down side is I don't like seeing the ice cream and such rounded to the whole dollar with tax included. Less change. A lot of kids baseball grounds are the same way.