...
In my city, the few BTMs have a fee ranging from 9% to 14%-plus. The fees were lower until recently. It may be that when you add up all the costs (the machine itself, managing it (putting BTC in, taking cash out, electricity, rent, etc.), a very low fee would not sustain such a business.
To my knowledge the machine I have used DOES NOT show the fee either.
20% is very high. Even the normal 14% I see drove me to using Circle when I want to buy.
Thanks for confirming another machine DOES NOT show the fee. I keep meaning to try a BTM, and this thread has given the good advice to do a small test transaction first so you don't get scammed by unstated high fees. Do you have to wait for a long time for your transaction to go through? If you do it could put people off doing a test transaction.