I've been in the space for the same amount of time and I'm not at all surprised by this.
It all comes down to risk tolerance for both parties involved. On one end of the spectrum, CPM models put ALL of the risk onto the advertiser, and CPA is at the other, putting ALL of the risk onto the publisher. CPC falls in the middle.
Depending on who has more leverage in the negotiation, what is possible for one advertiser may not be possible for another. But given the low-quality traffic I've seen on some publishers, and specific instances where I know publishers were arbitraging $.01 CPC clicks into their inventory counts, I'm not at ALL surprised they are clinging to CPM as long as they can. Their very existence depends on it.
High-quality publishers have little problem going with CPA in cases where they can control more of the funnel (which is often the weak link), and they can command a much higher spread as a result.
It all comes down to risk tolerance for both parties involved. On one end of the spectrum, CPM models put ALL of the risk onto the advertiser, and CPA is at the other, putting ALL of the risk onto the publisher. CPC falls in the middle.
Depending on who has more leverage in the negotiation, what is possible for one advertiser may not be possible for another. But given the low-quality traffic I've seen on some publishers, and specific instances where I know publishers were arbitraging $.01 CPC clicks into their inventory counts, I'm not at ALL surprised they are clinging to CPM as long as they can. Their very existence depends on it.
High-quality publishers have little problem going with CPA in cases where they can control more of the funnel (which is often the weak link), and they can command a much higher spread as a result.