Booking.com - the biggest travel website in the world, already does this and has been for years. They mainly charge via greater conversion fees (ie a bigger slice of the booking), as opposed to a cost per click model (which I think is Amazon’s preferred model). This way, they have a huge incentive on making the ad as relevant as possible, otherwise they’ve wasted inventory through not monetizing the click at all (whereas cost per click means you make money regardless of wether the user clicks through).