The refund policy was only implemented after Australian courts told Valve they had to implement a refund policy to follow default consumer rights law

They made it available to everyone because they were going to lose that case everywhere but the USA (where you have no rights)

Before that, Valve did not allow any refunds.

I like Valve for being slightly not outright evil and providing a service that is not trying to scam me, but that's such a low bar.