Um... Gav...
They don't use coins in slot machines anymore. If you have any cash, you have to load it in a card... and your winnings are stored in an account, where you later cash out on an ATM type machine which would give you your money in bills...
So in theory, if Suzy was to cash out, she would not get 500 pennies from paying in the penny slots... She'd get a $5 bill.