

That’s a field in data science / marketing that’s been active forever… assume that companies at large have a rating of their prospects & customers & ex-customers alike which includes a notion of wealth. Either derived from consumption habits or acquired through data brokers or both usually.
Depends of a lot of factors. Best case that’s enough. VPN isn’t generally doing much beside obfuscating network of origin and that’s not accounting for leakages. There’s stuff of the nightmares with pixels and cookies cross feeding data from a session to another… And tools like kayak might themselves have incentives to profile you as well. I don’t know that one particularly but in the end if you’re not giving money you’re likely giving data to someone…