...The actual service plan is terribly expensive if you see what it entails...
Without paying for a Service Plan you can still get free repairs under the warranty.
However, Tesla does not have to do any repair until a problem flares up and by that time you might be stalled on the road.
With a Service Plan, Tesla fixes things that are proactive and not even covered under the warranty.
Both of my FOBs were severely worn out cosmetically but they were functioning perfectly but Tesla replaced them for no charge. They were not broken so technically the replacements were not covered under the warranty. That's hundreds of dollars right there.
The cover under the front bumper and the frunk were severely scratched because I first didn't appreciate the use my Air Suspension properly and Tesla replaced that for free while that would cost others hundreds of dollars.
Tesla proactively switched out my 12V battery even though I got no symptoms/warnings from it and my VIN was not qualified for any Internal Service Bulletin. It's technically not broken and the replacement could have costed me another few hundreds of dollars but I've been doing this annual thing for 3 years and each time the bill is zero!
In addition, if I didn’t bring my car in, I wouldn’t know about Service Bulletins that gave me a free set of floor carpet upgrade and they installed a free upgraded bigger pair of windshield visors for my classic Model S.
Ok! Too much "free" but just like "free" Superchargers, it's technically "included" in the Service Plans/Agreement pricing.
So take your pick:
1) Free warranty and passively wait for your car to stall on the road
or
2) Pay Extra and pro-actively maintain your car.