My daughter has been traveling in Eastern Europe and Turkey for the past month. She's a backpacker and doesn't spend a lot, a little over US$1000 in that time for food, hostels, train and bus transportation, and spending money.
Today I saw her Wells-Fargo checking account statement, which showed US$94.94 in international ATM/debit card fees over the past month, including $55 for 11 ATM withdrawals and the rest in 3% fees on debit card purchases.
So the international bank fees came to over 9% of her total expenditures!
She could probably manage her ATM withdrawals more efficiently, getting larger chunks of money less frequently, but when you're traveling from country to country you don't want to get too much local currency at one time since you're soon moving on to another country with a different currency.
Anyway, this is just an example of the ridiculous amount of fees the banks can and do charge on international transactions.
We're gonna be switching banks!
P.S. By the way, my daughter says she is finding Eastern Europe and Turkey generally inexpensive to moderate, certainly less expensive than Belize for budget travel, and not much more than Argentina, Bolivia and other South American countries she's visited.