Well, never drive out of phone range then. While there's a 97% population coverage, it drops to 80% for roads, and less than 50% of the area of the mainland 48 states. Not to say anything about Alaska and most of Canada, of course.
If you drive a lot around the country, losing coverage is something you get used to. And that includes BMW Assist, AAA and 911.
In most of Europe, there's a close to 100% geographical coverage, so it makes more sense to drop the fifth wheel. But in the US and Canada, I think they should have provided a donut, even with runflat tires.