While I agree with your overall sentiment, I think the issue with this particular situation is that Wakemate was not being totally candid about their pricing intentions. Even after the recent announcement, nowhere on their site do they inform the user of the possibility of premium monthly subscriptions. If I were to have just visited their site for the first time, it would be sensible for me to assume that I am getting the entire product/software package for $50. Go see for yourself. I imagine people who did go for the pre-order did so under that now false pretense; so it's perfectly expected to see this sort of reaction. You are promised "the WakeMate, the cell phone accessory wristband that lets you sleep less and feel better!" with a barebones feature tour and that's it. Had they been more direct initially, I doubt we'd see this negative response.

I'd like to also add that there is absolutely no way for me to reach their recent announcement from the Wakemate website. Pricing is a serious issue and yet announcements pertaining to such are being made on a Heyzap founder's posterous page? Put that on the front page of your site else this problem will persist and customers will purchase your product not fully knowing what they're getting into.