I guess the idea is how much it's worth to you when you apply what you have learnt.
If you charge less than CC, or it doesn't get you into some nice homes you wouldn't have got into then it probably isn't worth it.
Then you've got the what you could LOSE factor if you don't do the training and feel you can blag it only to make costly damage.
Then there's the piece of paper you get at the end of the course which to some is very important for lots of reasons.