I mostly agree with you. The mine run rental BD from Blockbuster or Redbox will indeed give you a movie viewing and listening experience that is indistinguishable from the retail version. The only exception to this general rule I've seen has been on a couple of Rental BDs that the studios crippled with Lossy audio. Another difference is that some retail versions of movies have two discs, the second of which has the extras. On single disc retail editions, however, my experience has been that there is no difference between them and the rental versions.
All of that said, though, I virtually don't rent BDs anymore. If it is a film I am genuinely fond of, I'll spring for the retail version and if it's a film I am less interested in I'll wait for it to show up on one of the premium movie channels on cable. Streaming is a nonstarter, at least for me. Even if the new compression algorithm will accommodate streamed 1080p video, compressed audio no matter what algorithm is used, is by definition lossy and not lossless. No thanks.