As a non-American always buying non-rebranded and unlocked phones, this was my first thought as well.
But if I put on my tinfoil hat, how much crap has Verizon put on their phones? I'm not sure how likely, but it's not impossible to either have an app use up your data, or alter the data stats.
I suspect that any Androids approved by Google (which they need to be to have the play store preinstalled) aren't allowed to mess with the data collection, but the agreements aren't public so I don't know for sure.
(I think one was leaked in the Oracle lawsuit or something?)
But if I put on my tinfoil hat, how much crap has Verizon put on their phones? I'm not sure how likely, but it's not impossible to either have an app use up your data, or alter the data stats.
In any other case, I fully agree with you.