You're not alone. A lot of people will invest a lot of time into lying, playing dumb, making threats (think people with a lot of Twitter followers threatening to broadcast how terrible your company is unless you give them exactly what they want) and other manipulative tactics to abuse warranty claims.
Ultimately this is why we had to become more strict about warranty claims. When half of your warranty claims are coming from people angling for free upgrades or demanding full-price refunds after many years of service (some of whom tried to demand to keep the hardware and get a refund), you quickly become numb to it. I guess companies like Apple can absorb the lies for a while, but eventually you have to make a choice between padding your margins to cater to the warranty abusers or becoming more strict on warranty claims.