they charge at least 10% commission +other fees trust me i asked them !...
How many ATM owners did you try to ask?
At least you tried it with 3 different owners to make sure about the commission fee. There are some ATMs only ask for a 2% to 5% commission fee you might just be unlucky today to find them.
How about the list from here
https://bitcoin.org/en/exchanges#north-america I hope some of them will work with less fees.