Oink filled a void at a perfect time in music.
I grew up in the 90's and CDs typically ran in the $15-20 range. This was when minimum wage was something like $5.15 an hour. So it would take 3-4 hours of work to buy a CD. This led to having to really pine over purchase decisions. Pre-Napster, this meant using a few things as filters: the radio, label compilations albums that featured a lot of songs by artists and were usually cheaper to buy, or pirating via IRC, which was fun at the time, but looking back was quite tedious.
Then Napster came and went. In it's wake, consumer expectations changed but nothing really worked as well as Napster. It's replacements were unreliable, were risky for installing adware/spyware, and there were lots of scare tactics by the music industry going after downloaders in court.
This was also around the time of the iPod but pre-iPhone, so you could carry around digital music but it wasn't really streamed. At this time, I had an iPod but mostly consumed music in my car through burned CDs.
Enter Oink. Oink brought you back to the time where you consume full albums instead of single songs but also solved a ton of problems with music sharing programs -- the shady software, unreliable availability of songs, inconsistent, if not totally absent tagging, shitty encoding, etc. Since there was still some work involved in downloading and burning the albums, you had to still make some choice over what to listen to, but not labor over it like a few years back when a CD meant half a days work. Oink had SO much stuff as well. I cannot recall a time when I didn't find something I wanted. Even though it was stealing, it felt like you were getting something of quality and not taking a gamble on something from a music sharing site.
I don't really recall what I did with music from Oink's shutdown in 2007 until Spotify came to the U.S. a few years later. I got my first iPhone in 2008 and buying music from the iTunes store became much more appealing with it instantly showing up on your device, so I did more of that. I remember using Rhapsody on Desktop for a while and later on the iPhone as well, a year or so before Spotify took over music.