Honestly, I think a lot of what you are paying for with the boot camp is the promise that their network and industry contacts will help you. Otherwise it's pretty much impossible (at least in my view) to justify those tuition rates.
Not to say this would or wouldn't justify various tuition rates - but it's definitely part of the equation.
But yes look at placement rates at any bootcamp before joining. If people are getting jobs then it's well worth it.
But yes some people have plenty of self motivation and can do it themselves. The career networking is really all they need then.