Well let's put it another way. Cadets could be putting money into university for no guaranteed job at the end or they could take out the debt and have a guaranteed job which will pay around £100k a year with Ryanair. Sure they will treat you like **** but honestly, the entire jobs market is rubbish, not just aviation. Sure the unemployment figures are low, but many of those jobs are zero or low hour contracts. Even if they aren't being paid as much as pilots were 15 years ago, it's a hell of a lot more than they could be getting otherwise.
For them they are getting a chance to earn big money. It's only the ones who were earning bigger money before that are complaining. I'm not saying it's right, but that's how it is.