BD (just like DVD) is a proprietary format and license fees must be paid to the rights owner if you want to legally release a device or software capable of playing the official format. That's why there are so few legally free alternatives, or rather, none. Either you pay or pirate. Though paying might have happened if you got a retail packed drive (or laptop with a drive) and some software was thus included in the package price.

A couple of years ago I was still thinking of getting a BD drive for my computer, but slowly I've let go of the idea. It's easier to watch the movies with my regular standalone BD player of the home theater (I don't have PS3) and burning optical discs is kind of out of fashion unless you are burning video BDs of some holiday trips, family events, hobbies, or whatever.