your comment reminds me of a text I read a long time ago, comparing humans to ants and pointing that we're incredibly intelligent when alone, but we become less and less intelligent when in bigger groups, while ants seem not very intelligent when alone, but when in groups, they seem amazingly intelligent
Maybe they won't suggest things you already bought, but will estimate what you're going to buy next, based on the statistical analysis of people who bought the same things.
I can rotate one finger at one direction and the other on the opposite direction while pointing one to another, simultaneously. I don't know how uncommon it is but, back at high school, no one else in my class could do it. Totally unuseful skill.
It can be gross from a human perspective, but at least the ant is unharmed, right?