It's useful to some things, esp. when there is a high value potential click conversion, i.e. amazon and ebay items. Some ads are bought by brand advertiser wit

It's useful to some things, esp. when there is a high value potential click conversion, i.e. amazon and ebay items. Some ads are bought by brand advertiser with little understanding of the impact because a) it's 'brand' and hard to measure in the first place, and b) they have a huge budget, need to spread it across channels, so they just 'buy X$' of 'social ads' on the 'trusted networks' because that's the marketing mix required of their bosses or client. To be fair - print and TV ads have the same problem. Marketing is not a hard science in many places, and they have big budgets :). But it clearly works for some folks. There should be no surprise at in-links from reddit: theres usually a degree of clear interest in the first place, and second, there is a 'voting' structure that naturally moves better quality stuff to the top of the pile.