Economic factors are the only indicators most copyright holders care about when it comes to DRM. The moment they can sell more copies without DRM than with, they'll drop DRM. And not a moment before.
Also note this nonsense is very acceptable to the majority of consumers, myself included. If you want to vote with your wallet and not buy the Kindle/iPhone/Zune until it drops DRM, more power to you. But you'll have to wait until those of us who are happy with the current arrangement have bought our fill and Amazon/Apple/Microsoft have to start looking for niche markets. Your complaining in the mean time is not likely to make an impact.