Except that there are various shades of them and most are posted up with T-Mobile in big letters then some talk about phones following that. Humans are lazy, They see a color, they see T-Mobile, they see talk of phones. Marketing knows this, marketing is about manipulation or we would have it because humans natually gravitate towards things that are better.
Of course they look different when posted right next to each other. It is very clear that AT&T was trying to make AIO look like T-Mobile in some of their marketing materials. T-Mobile is well known for being protective about the color magenta within the wireless industry.
AT&T played with fire on this one and got burnt. Not that it really matters, because AIO will be absorbed into Cricket at some point.