What happened to self-administered aversion therapy (with a rubber band in particular)?
Out of the basically four possible ways to change behaviors, your rubber band lies at one extreme, being an example of positive punishment, which works by presenting an aversive stimulus after an undesired behavior is exhibited, making the behavior less likely to happen in the future. 

There is also the lesser negative punishment when a certain reinforcing stimulus is removed after a particular undesired behavior is exhibited.

Further, there is positive reinforcement, which works by presenting a motivating stimulus to a person after a desired behavior is exhibited, and negative reinforcement where usually an aversive stimulus is removed after a particular behavior is exhibited. 

Now all three alternatives are less extreme than your example and, anecdotally, I do see a tendency toward a more positive approach in efforts to change behaviors, for example in parenting (i.e. reward rather than punishment). Less anecdotally, according to wikipedia, punishment indeed seems to be used reservedly in psychotherapy nowadays and is mostly reserved to the more extreme cases to reduce outright dangerous behaviors such as head banging or biting.