It's a feature of the changing employment market, and not just in aviation. Wheras a few years ago people would join a carrier expecting to stay for a long time - maybe life with the benefits of a final salary pension scheme, nowadays people are always going to look for the better deal. This has largely evolved from the practice of employers constantly seeking ways to reduce costs, but some of the blame has to lie with the employees.
The company I first worked for having left the military was an established long haul operator who people joined expecting to stay in until retirement. The pay was a lot lower than average, but people stayed because it was a fun company who didn't work you too hard, had reasonable command prospects and the job was apparently secure. But after Sept 11 when the company showed it's loyalty to it's pilot workforce by laying a quarter of them off, the perception of this company has changed. Now, pilots in that company will always look for something better, be it better renumeration, lifestyle or command prospects. Many (including myself) have left for other operators - something that had never happened before in that company's history. But they still receive a lot of CVs, have a fully functioning training department, get tax relief on training and are probably not worried about the situation.
If easyJet can find people to pay for their type rating, they will continue to offer this deal. Objecting to this on principle by not applying merely means you will not get the job. Someone else who is willing to be bonded for 5 years on lower pay is probably going to be more than happy with that situation. It may mean that they will look for different employment as soon as their 5 years is up, but as I said earlier - that is the nature of the job market now.
However, I suspect that easyJet are fuly aware that the supply of these people will dececrease if the aviation market picks up and they may well have to offer £30K 'golden hellos' again to fill their seats.