As far as the US goes, operators don't talk about it much but I think most of them are operating without a MT license at the state level, but registered as a MT at the federal level. Then there are what I call "gorilla" operators who operate low key skyhook machines that have not been publicly advertised.
...does that mean you will need a money transmitter license because FinCen says so?
Yes, you must comply with the FinCEN guidance if you intend to operate legally.
Wouldn't 1 way bitcoin atm's (dispensing bitcoins for cash but not giving out cash) be more like a prepaid card or vending machine? Since technically you are putting money in to get say a printed paper copy of bitcoin or transferred to your bitcoin address much like a gift card?
A common argument that operators make is that Bitcoin ATMs do not meet the definition of money transmission at the state level. Prepaid cards have their own set of AML requirements so that comparison is not ideal. Regardless of what you call it, the details of how it operates will determine if it is in or out of scope of a given states MT laws.
I have not heard of any arrests of operators either.
(this is not legal advise but I can recommend an attorney!)