This already happens on an extent on Delta's website. I've had it happen multiple times where I receive a higher upgrade offer price than others traveling with me on a separate reservation. Other times where even the price of the ticket is different, despite vehement denial from someone in Ed Bastian's office. Hence I frequently use incognito and change my VPN's location to search and get cheapest mileage-based offers since this isn't searchable on Google Flights. Quite scummy to think they're offering higher prices to their more loyal customers (I travel about 50k miles/yr on Delta). Makes me want to become an airline free agent since I'm in NYC and can get direct flights pretty much anywhere.