Doesn't the need for a Bitcoin ATM indicate that Bitcoins have failed to achieve utility as a currency?
I don't think so. We are bootstrapping a new currency. To make it viable, we need to make it easy for people to get into bitcoin in the first place.
Does using the ATM compromise any anonymity of the Bitcoin owner, and does it pose a security risk since the ATM will have interacted with the Bitcoin owner in a manner that allows the ATM to capture security information?
I could see anonymity being mitigated by the use of cameras either in the ATM machine itself (as most ATM's have them) as well as cameras in the location of the bitcoinATM, like a store, airport, train station, etc.
As far as anonymity in the blockchain goes, no, I don't see this having any effect. You could generate a bitcoin address at home, print it to a QR code, and then deposit cash in the machine and let it scan your printed QR code. No where in the system would your real name or info be used. But like I said earlier, there may be video evidence that you used the machine, which to a well equipped investigative agency, could potentially identify a person and where their bitcoins went.