There are limits as well. Olathe Subaru in Kansas (where I purchased from) has the lifetime powertrain included in all of their new car sales. It is limited to $6,000 and looks like you need to keep good documentation of all of your service. Additionally they require that the oil be changed at least every 6,000 miles. Synthetic can go 7,500 between oil changes so make sure you read the fine print.
I plan to keep my 13 past even my Subaru 100K extended warranty as I will have new drivers in the household in 3 years.
I doubt these policies rarely pay out, but hey if the CVT goes out at 110,000 miles I have a chance of coverage (assuming dealer still here or company that wrote the policy)