I have never had to add the #1 to any of my contacts to be able to call them. I think Verizon handles all that when needed. I call all over the USA and have never had an issue in doing so, minus the 1.
The default for all cellphones for numbers is that you do not need a '1' in front of the area code. You can actually dial the number with the area code included. 1 is only handled by the wired phone system.
You can also dial a number with the '1' in front, but the Cell system, and other systems tend to ignore it. Most Wired Phone systems assume you are first dialing local before Area Code, Cellphones, given the lack locality, will assume a number 10 or more digits == Area Code + Number, otherwise, it will assume local.