According to the article, the remote start feature from the remote does not use the cell connection.

A remote RF device could do that without the Sim card, the same key that unlocks the car... My problem is that I paid for a device (the starter device already installed on my car) that I can't use without a membership. People have had remote start on cars for decades without needing a bloatware subscription to XM radio.... sigh

That might very well justify some fee, but $8/month is excessive if one only cares about remote start.