It was then found that it also steals all commissions at those checkout points, and instead of finding you a "best deal", it colludes with the merchants, allowing them to control how many people get what kind of "deals", completely defeating the point.
This is how "deals" have always worked, to the extent to the current technology makes it possible. Companies don't issue "deals" to be pro consumer, they do it because it benefits them, and they do it in ways that benefit them. For example, they would mail coupons two a few zip codes but not actually mark down the prices unless you actually possess a coupon. That's just a low-tech version of what you're describing.
I'm honestly surprised that people are surprised by this aspect of Honey. The hijacking of affiliate links is one thing, but coupons have always been a way for businesses to influence consumer behavior. Who did people think Honey's real customer was, given that the extension is free?