Tips can be paid per post, per comment, or per space. Not only can post authors get paid, but good comments / replies can be rewarded too.
Similar to tips on YouTube's Superchat – it is possible to use tips to highlight users’ comments. Highlighted comments stand out compared to the free comments such that content creators will notice those comments first. If the creators have thousands of comments per post as we see with people like PewDiePie, highlighting will make a user’s comment stand out.