Suppose people saying quality isn't important are watching the beautifulest movies ripped on screener version on their cellphones screen; and read Shakespeare on awful supports with muddy typo(and for foreigners, with a terrible traduction).
If you like the vibe and just want to do like your friend, i mean "yeah man good vibe i listen to that too", i suppose 128k will be far enough.
If you really love music and listen carefully to it, god there is no way to say there is no difference between a shitty ripped mp3 and a wave/flac.
If you are a producer and listen only to poor quality mp3, i guess i have some really bad news.... You are missing so much...
With the poorest quality, i would say that you can't hear like 30%(even more) of the work that has been done by the artist... i mean wtf. You watch "half" a Da Vinci painting? "yeah the top layer of the Joconde is quite good mate i love it too".
Shame seriously.
I admit that i listen sometimes to shitty quality tunes on youtube or other support. When i love it i look for it on good quality.
BTW f*ck you tube as a music support. Good for staying tuned on what is released. it stops here.
My POV tho.