I dont think its a waste.....but if one is put off by the 'spirituality' aspect of it, they had probably better be pretty good at alternative solutions. I was more wondering if there are alternatives....or maybe they are simply pretty much all one and the same thing.
As for behaviour modifications - I too think they can be pretty easy to achieve, and can be relatively quick, the hard part is working out what exactly you are trying to change, and the best way to do it without unforeseen consequences. The jail example is a classic - it is a behaviour modification experiment. You have to adapt quickly if inside, and then this behaviour does not translate well to the outside again....unless done in a different way jail seems pretty much a poor solution for many.
In order to change deep seated beliefs - much the same - you need to understand which ones cause problems....or if they cause problems at all.
There are flotation tanks. There is biofeedback. There is therapy.
I'm not an expert on meditation. I would suggest that there are many different versions of the same thing. If you were to choose a method I would go with the one that most naturally appeals to you. Some people respond to giving over to a higher power, some like have a teacher, some like ritual, some like discipline etc. Pick the one you will do.