Being in the content game, it's because it's totally not worth littering pages for the 5 cents a month it'd make. I'm hyperbolizing, but even if it were $100/m

Being in the content game, it's because it's totally not worth littering pages for the 5 cents a month it'd make. I'm hyperbolizing, but even if it were $100/month, it wouldn't be worth the space. What this space needs is someone with deep pockets to subsidize the publisher growth until the critical mass of users is reached.