It's not the first time in history where everyday people contribute to a very inhumane industry. These industries are usually not perpetuated by consumers who want to be evil. They are perpetuated by consumers who are somewhere between uninformed and complicit, usually somewhere in between.

I don't think that the average meat eater is a monster. It's very normalized to buy factory farmed products without knowing and thinking about the cruelty that animals had to endure for it.

Many people know that there are instances of cruel treatment, but assume that these are just a few bad apples and that this has nothing to do with the products they buy. This is partly wishful thinking, partly complicit, partly just too abstract in their head to influence buying decisions, to varying degrees.

If someone knew quite a bit about the unimaginable suffering caused by the industry though, and continued funding it without thinking "well, that's not good, it would be better if I would stop contributing to that", then this is malicious behavior. What else could I conclude?

So I would attribute varying responsibility to the consumer, based on how much they know, and on how easy it would be for them to choose alternatives.