Unsolicited, mindless trivia interjection:
So, why do we have "piggy banks"?
For centuries before commercial banking was available, people simply saved their money at home in a box or a jar.
During Tudor era, money was often saved in small , orange clay jars with a slot just large enough to insert coins. This orange clay was known as 'pygg' clay (originally pronounced 'pug').
You can see where this is going... As money jars and the English language evolved, even though the banks were no longer made of the special clay, but the name stuck.
Pygg banks became Piggy Banks over time and were eventually even made in the shape of pigs.
One thing didn't change, though. To get the money out you still needed to destroy the bank. So, if you had a great expense you had to "break the bank" to pay for it.