It's really not at all. In Japan, you just buy a debit card and swipe that every time you enter or exit a station. When it gets low, you stop at a vending mac

It's really not at all. In Japan, you just buy a debit card and swipe that every time you enter or exit a station. When it gets low, you stop at a vending machine and put more cash on it. It doesn't get any simpler, and it's totally anonymous.