I think that this Social Proof is one of the most important factors we take under consideration, also in the internet - how often do you check google search results that are not on one of the first three pages?

And in this case it is also not hard to show that such behaviour is not a winning strategy, if you want to maximalize your chance to make the best choice. But still it seems to be a winning strategy, if you want to avoid making the worst one.

I think the catch here is that people tend to think that they in fact want to make best choices and not just avoid the worst ones.