What are "rewards points"?
It is possible for you to reward an answerer 5 points for a "helpful" answer or 10 points for a "correct" one (or none at all). Users who accumulate certain amounts of points reach different levels of recognition (see legend). In this manner, users who offer consistently helpful or correct answers raise their standing in the community. (Note: in order to award points, you must identify your post as a "question" first - which is set as default.)
So where do people cash in their points? Just curious.
I'm also not sure right now. I got thrown out of the last bar where I tried to pay with some of my points, and also the coffee dispenser constantly ignores my offer of even all my points for one small cup.
Seriously they don't have much value. With X points you get another badge displayed right to your handle, and also if you are in the top X of a forum you get displayed in the top participants list of the forum (much similar as with the post count previously). Other then that they have not much value.