How to avoid Carplay Maps data usage?

I just started using CarPlay on my new car, and noticed within 15 minutes my mobile data usage had been seriously used up. I am someone who uses VERY little data usually (WAY less than 1 GB a month) since most the time, make sure am on WiFi, not an option in a car), but this truly wipes this out. I see that there is no way to disable Apple Map from the list of apps. I also notice if I turn off CarPlay and ask Siri to navigate, data usage is negligible.

So, 2 questions…why this huge difference, and is there a way to NOT have Maps actively running when I connect CarPlay so as to avoid having to needlessly pay for data usage.