To be honest, brand awareness and brand reminders kinda do work. I occasionally like to go to McDonalds. It's late at night, I know they're open late. I'm pretty hungry, I haven't eaten today. I wasn't thinking about McDonalds before I read this thread, but for a second there, I seriously considered walking over. Did they sell me? Not this moment. Did they maybe sell a few hundred people now that they got in their brains? Well, as long as the margin is worth it, marketing works.

I don't do anything with social media but I work for a marketing/analytics company. Just reminding people of brands is one of those weird "you wouldn't think it works, but..." You don't even have to pimp your products, convince anyone to buy anything, literally just remind them that you exist.