This is all true but the question is at what point of scale does the cost outweigh the benefits?
At small scale, you get more money (in absolute terms) using price discrimination with no validation on the back end. As your scale grows, you reach a point where it's worth the monetary and time investment to add validation and things on top.
At the end of the day someone using a VPN to get your product for $5 instead of $20 doesn't matter that much unless you're so wildly popular that people are clamoring for it, at which point you theoretically have the staff to start adding in some protections.
Another factor is considering how difficult you're making things for your legit paying customers just to may sure you keep someone somewhere from ripping you off. A lot of companies strike the wrong balance.
At small scale, you get more money (in absolute terms) using price discrimination with no validation on the back end. As your scale grows, you reach a point where it's worth the monetary and time investment to add validation and things on top.
At the end of the day someone using a VPN to get your product for $5 instead of $20 doesn't matter that much unless you're so wildly popular that people are clamoring for it, at which point you theoretically have the staff to start adding in some protections.