bscar; you made a good point. The things covered rarely break, except through negligence or abuse. If you subtract all normal wear and tear and maintenance expense from the lifetime cost, you would not have much left.
On my 1988 Caprice there were:
Water pump failures (2) $470
Heather core failure $225
Intake manifold gasket failure $255
replace starter $334
Heater fan motor failure $55
Rear differential bearings $450
So a total of $2179 over a 19 year period and nearly 200,000 miles.
Of the above the warranty company would no doubt call the starter and alternator replacement as normal wear and tear.
The $2171 quoted to OP is for only 36,000 miles or 3 years. In my case that would be 36/19x12 times the $2179 or $344 of claims for the 3 year period. At the cost quoted, the payback would be only 344/2171 x100=15.85% of the money spent.
Consumer Reports lists the Infiniti as having a much better repair record than the Caprice, so the claims rate would be even less although the cost per claim might be higher.