Surrounded by ads

The mobile phone market has fierce competition? How they compete? with Ads.
On CTA trains, riders are surrounded by ads of Verizon, Cricket, US Cellular. Each company buys ads for the entire car, to ensure you are surrounded. Ads are even at the ceiling! There is no escape unless you look down or play games on your phone.

Of course each company boasts best value, best service, etc. Customers deserve proof. Is there a Consumer Report or something that objectively compare head to head with features, services, price, annoyance of spokeperson icons, etc?

Here is what customers want:
1) COVERAGE. I used to have Verizon and I can't get calls in Chinatown, COME ON. Even if they improved it now, it is too late, I switched.
2) PRICE.