There's also another side to this story: headhunters benefit from "selling" developers at a high price, and usually they are way better negotiators than the ave

There's also another side to this story: headhunters benefit from "selling" developers at a high price, and usually they are way better negotiators than the average developer. Most of the time, that money saved doesn't go towards a signing bonus or a salary bump, but stays in the pockets of the employer. Also, if you're confident about your development skills but not so much about your interviewing skills, having a good headhunter basically doing the initial salespitch for you can be very helpful.