For those unfamiliar with the game's pricing system, the points I was refunded would usually take a few nights worth of playing to earn . They can be used to buy new champions or runes (which allow you to customize your loadout). Since I can spend these points in lieu of paying money to buy things, Riot are trading a little bit of cash in the immediate future for my long term goodwill. They also really made an effort to do this by searching their sales logs, because I purchased this champion at least a couple of months ago.
This kind of thing is ALWAYS a good investment in my book (see: Valve).