I don't think Tesla is saying you have to buy the additional 4 years of service plan. They are saying you have to have annual maintenance. You could still pay as you go and comply with the extended warranty.
Tesla is sending mixed signals. Per Elon Musk's 4/26 blog post: "… we are comfortable making the
annual checkup entirely optional. There is still value to having Tesla look at the car once a year for things like tire alignment, to address a few things here & there and perform any hardware upgrades – our goal is not just to fix things, but to make the car better than it was.
However, even if you never bring in the car, your warranty is still valid."
Here is what it says in the ESA: "You must follow correct operations procedures and have Your Vehicle serviced as recommended by Tesla. If requested, proof of required service, including receipts showing date and mileage of the Vehicle at the time of service, must be presented before any repairs under this Vehicle ESA commence. Service within 1,000 miles and/or 30 days of Tesla’s recommended intervals shall be considered compliant with the terms of this Vehicle ESA."
The two seem to be in contradiction to one another. Elon says you never have to bring in the car and the warranty is still valid, ESA says your extended warranty is only valid if you service your vehicle within 1,000 miles or 30 days of Tesla's recommended interval, and that Tesla can you ask you for documentation that you serviced the car per Tesla's recommendations - which Elon said on 4/26 you don't have to do. So I am not quite sure what to think other than to defer to the actual written ESA language. At its face value, the ESA will require you to have annual checkups as recommended by Tesla. For those of us who were not planning on utilizing Tesla's annual service on a regular basis, the ESA will cost an additional $3800 if you get the 4+4 service plan or an additional $4,800 without service plan (no discount).
So for those of us who were not counting on spending the additional fee for annual service, the ESA is essentially going to cost a total of $6,300 in order to maintain its validity over 8 years, and that's if we pre-pay for service in advance and buy the ESA at the lower $2,500 price. There are owners who are going to want to rotate their own tires, change their own wiper blades, and not take the car for a full check-up each year. For those people - and we are out there - the ESA is going to cost a lot.