Replying SOLELY to its use in Psychology,
At best, it's a band-aid solution.
With compulsive behaviors troubling the patient, it is possible to use hypnosis to TEMPORARILY mask a symptom, but then therapy must take over. The hypnosis, at best, buys time to continue treatment and get lasting results.
That having been said, for anything less than that, I consider using hypnosis or other forms of mind control to be akin to using a hammer to kill a flea. It's not good for the mind for someone to try to hack into it.