I have had this happen with my on 2 eyes. Whenever I look for flights I will go through a VPN, but also have used different computers with different OSs. I've saved hundreds of dollars on some trans-atlantic flights just by getting my wife to book through her work computer.
We have had 2 laptops sat side by side on the same wireless network, both running OSX and one will give a higher price than the other due to search history.
There have been independent investigations in to this and the legality scrutinized, but it turns out to be perfectly legal. Lots of cases where fliers sent though house doors quoted different prices due to the relative affluence if the neighborhood. As long as there is no discrimination based on age/sex/gender/race etc. Then companies can dynamically price in anyway they want
And this is the next stage for all retailers. Ultimately the people behind surge pricing are looking to bring in individual pricing into being in the future.
"Oh Mr knapstaad, my system system tells me you quite often buy 4 titan cards and are wealthy, our new Titan is therefore £50 more to you sir"
Thats the kind of world we are heading to.
Ultimately in shops with the digital displays they will know who you are standing in front of it and it will show a different price to you than the next person going to that display.
For example, they might know you always buy a certain brand and they might off you an instant discount on their own brand to get you to buy that instead of your normal brand. This discount would be for you only.
but is to respond to supply and demand.