As long as they don't alter the search results to give those links an advantage, I have no problem with them using affiliate links. It makes them money to absolutely no loss to me, right?
If for convenience I search for "Amazon product X" on my browser bar instead of directly on Amazon, that means that in order for Amazon to generate a certain amount of profit on that product they also have to pay my search engine now, which means all other things equal, this costs me money.
Of course in real life it's not that simple a situation but it's easy to see that everyone behaving like this ends up with the consumer essentially losing money.
From what I understand, affiliate links pay out only when you buy something. Traditionally, this was taken from the seller's margin and the price of the product was not increased, as the higher volume of sales made up multiple times for the loss from commissions.
But since Amazon gets nothing from the "passive" affiliate links (ones that don't increase volume), DDG might be big enough to make them have to compensate. Would be interesting to see the numbers for this...
That's fair, but the Referrer header already does that. It can be blocked, true, but either way this is just a single literal bit of data - I don't mind, but I see how someone might.
An argument could also be made, that this is beneficial to me, as if Amazon finds a lot of traffic from DDG, they might be more inclined to buy ad space with them, giving better funding to a service I like.
The HTTP Referer header is a horrible bug that should never have been part of the web IMO. When I tell laypeople that this happens they're often very surprised.
Of course in real life it's not that simple a situation but it's easy to see that everyone behaving like this ends up with the consumer essentially losing money.