I agree IT unions aren't very necessary. We have it easy; we're well paid, we're fairly flexible, and if one employer sucks, we can easily can a better job elsewhere.

But plenty of industries don't have that advantage. Many workers are very dependent on a single employer. This is especially the case with workers that have highly specific training and experience that doesn't translate well to other jobs. If they're exploited or otherwise unhappy, they can't simply quit and get a similar job elsewhere, whereas the employer can afford to lose a single employee and train a new one, which makes the employer-employee relationship an unequal one. There, unions can provide a lot of value to keep employers honest.