Did you have to give ID to buy them at an ATM, and did you pay with cash? I have never used an ATM before. Where does the price you pay come from, is it based on an exchange's price?
The ATM that I use regularly (Bitaccess) does not require ID, just a phone number to which it can send an access code via text message.
You then enter the code into the ATM and you're ready to buy or sell bitcoins. If you don't have a wallet it will create a paper wallet for you, or you can scan the QR code of the public key of the wallet of your choice, be it a paper wallet or a wallet app on a phone or other mobile device.
The price is determined by bitcoinaverage.com +/- a fee for the ATM operators. This fee is usually between 5% and 7.5% depending on the operator.
I've never had a problem with it yet. The main drawback is the fee but if you consider the exchange fee, the cost of transferring fiat via a bank and the time it takes, it's a small price to pay for the convenience and instant service, especially for smaller amounts.
An added bonus is that the transaction is as anonymous as the phone you use to receive the access code. There's a limit of $3000/day per phone number to comply with KYC/AML regulations, but that isn't a problem if you have multiple phones.
Only cash is accepted and dispensed, no credit/debit cards or other plastic.
I hope this helps.