Purchasing a Tesla means some double-digit percentage of your cost is going to fund Research & Development of future products, and making manufacturing more efficient. Where else would the money come from?! Realizing this, it's still a bit bitter pill to swallow, but I'm fine with it given the amazing work they're doing and what they're coming out with.
Also realize that, as long as you replace it with another Tesla, you yourself will be benefitting from that donation in the form of a better, lower-cost car when it's time to refresh.