You can check the bitcoin ATM providers and the amount they are charging as fee. It is always expensive.
But anyway if Bitcoin ATMs have a high fee and are more expensive. So why don't we need to do a P2P exchange rather than an ATM exchange. Because if we look at the Bitcoin ATM fee so it is quite expensive. There is a 10% to 23% fee on average transactions, it depends on the county, but actually used this fee.
So i think if we use p2p instead of ATMs, which directly transfer other people's cash up it will not be better. Because firstly, you pay the Bitcion fee and then the transaction fee and then the fee of the fiat currency, so it all becomes quite expensive.
So, in my opinion, Bitcoin will be less expensive in p2p exchange than ATMs. As of now, the world has not gained enough adoption compared to Bitcoin's fiat currency, so its service charges will also be higher in comparison to the lay ATM.