This is inaccurate. You are not buying it (the media), you are buying the right to stream it (as long as the seller provides the media as a stream). You don't "buy" a movie unless you are paying for it's ownership, which would be millions of dollars. For physical releases you buy the disk and the right to watch it under certain conditions (DRM). And you generally don't have a right be able to "buy" or have access to all media.

But all that doesn't automaticly make it amoral. ~~this comment is gonna be downvoted to hell~~

edit: There are probably gonna be more responces, so this will address everything else I have to say. What I wrote is how things are legally, more or less. I don't like that either. I do consider piracy stealing (under current laws) and morally right. Stealing is just not that great term for digital stuff. Please don't try to (uselessly) sway me and don't infight