That's interesting. Are they actually using personalization to get better prices? I'm thinking of scenarios where if two different browsers visit the same page

That's interesting. Are they actually using personalization to get better prices? I'm thinking of scenarios where if two different browsers visit the same page, they'll get shown different prices depending on their cookies etc. In that case, a third-party site can't really "route you" to a lowest available price, they have to help you make the purchase from the right browser environment.