Off topic, but I've been wondering for years about people pricing things with a 7 in the end (497$, 597$, 197$...) Every "web marketing" person I ran into does

Off topic, but I've been wondering for years about people pricing things with a 7 in the end (497$, 597$, 197$...) Every "web marketing" person I ran into does it, it comes from that environment? It's something considered to result in more sales, or maybe a way to signal that you're connected to some web marketing guru?