Ogg Vorbis has a good reputation for code when streaming but as you say, it is not Hi-Res.
I have started to make jokes about Spotify about 6 months after they've 'announced' that Hi-Res is in the pipeline, years ago and nothing happened. Ever since it has come up sporadically, every six months or so on the Web and ... nothing. It is what it is but imho it is now uncompetitive price wise and for performance if you care about sound.
Having said that, I am not amazed anymore about how much so called Hi-res recordings sound abysmal and how some plain jane CD quality ones can sound staggeringly good. Point is, I like the option and/or the possibility to listen at the best possible quality even if it is hit and miss.