If you're not getting paid, you're not doing "business".
Yes, there are many other examples of companies having exploratory practices the same way as Spotify. That still does not explain very well why people put up with it.
If a farmer exploits a migrant worker, the migrant worker gets paid enough for shelter and food. He is depending on that job for surviving. When artists are exploited by Spotify, the money they usually receive is nowhere close to paying for shelter or food, so they have to survive by other means anyway. Keeping their music on Spotify or removing it from Spotify doesn't make any difference for their livelihood.
Because the other thing Spotify gets them is exposure. Whether or not it's worth what they have to deal with from Spotify, I have no idea—but I can absolutely see many artists putting up with it in hopes that being heard on Spotify will get people to buy their merch, come to their concerts, etc.
Musicians/DJs/etc. also often do corporate gigs to eat. I'm sure they'd often much rather be playing for passionate fans in a bar than playing at some event where half the time the attendees are largely ignoring them except to wish they would turn down the volume so they could have a conversation.
Somewhat different situation than the Spotify case which is arguably mostly an advertising channel while corporate gigs actually pay directly. But creatives of all stripes doing things they'd rather not do so they can live, do what they want to do, and have a sliver of a sliver of a chance to breakout is extremely common.
If you're not getting paid, you're not doing "business".
Yes, there are many other examples of companies having exploratory practices the same way as Spotify. That still does not explain very well why people put up with it.
If a farmer exploits a migrant worker, the migrant worker gets paid enough for shelter and food. He is depending on that job for surviving. When artists are exploited by Spotify, the money they usually receive is nowhere close to paying for shelter or food, so they have to survive by other means anyway. Keeping their music on Spotify or removing it from Spotify doesn't make any difference for their livelihood.