Are you sure about that? It seems that businesses wanting this is both crucial to the idea, but also unproven. For example, consider two very close competitors in the widget-making market, A and B. If A adds this, then:
1) They might get better bug reports and be able to fix them better, giving a less buggy product and making them better than B - good for A
2) A user reviewing both A and B might see that A has a list of bugs, and (most likely mistakenly)assume since B doesn't have such a list that B has no bugs. They assume B is better - bad for A
I suspect it depends on a lot of other factors which of those results is more pronounced, but it is unproven which way it would go for any given business.