Fiction!
Whoever told you that had crappy cell service in the area!!!
I work for the best wireless carrier and can tell you there are many factors that come into play. #1. In Car coverage is not spread out in every single street. #2. Regardless of the tint you are covered by metal and glass so that will impair coverage if not strong enough. #3. Your cell phone could also need replacement or software upgrade to increase signal strength.
I can go way more into the semantics of it but who cares.
When looking at a detailed coverage map (Usually only employees have access to) you will find the following...
Best Coverage = In Building Coverage (meaning service is excellent in buildings, cars, and street. heck even on a small airplane flying low)
Moderate Coverage = In Car Coverage (meaning service will be good in the car and great on the street but slightly poor in buildings)
Light Coverage = On Street Coverage (meaning service will be poor in your car and especially in buildings)
No Service = No Coverage (Your SOL)