I don't understand why this is a problem for some people.

It doesn't increase the price or impact your buyer experience in any way, so why do you care? If this blog post introduced you to a product you wanted to buy, why should you have a problem with the author getting a finders fee from the seller? Just seems mean-spirited.

It impacts the buyer experience.

These two statements have a very different impact:

1. I love product X and I won't get paid if you buy it too.

2. I love product X and I will get paid if you buy it too.

Money motivates people to claim they love a product or that a product is good, even if not true. It's a problem that has plagued the internet for decades.

I don't think it's this binary.

Influence and power are far more intoxicating currencies than affiliate revenue.

And if someone complained "you're just publishing this helpful thing to become more influential in [community]," well, at some point we need to acknowledge incentives drive all behavior in one way or another.

Refusing the incentive doesn't make one per se virtuous.