It's not a "fad," it's called letterboxing, and it's a simple way of showing footage shot in 4:3 or other narrow aspect ratios. What you're seeing blurred on the left and right sides is not actually obscured footage, it's the same footage as in the center, zoomed in on and blurred so that they don't have to use a graphic to fill in that otherwise blank space. Some stations do use a graphic for that purpose, but the zoom-and-blur technique is generally thought of as a way to make the presentation more dynamic. Rather than seeing repetitive station logos and slogans which may not match up well with the content between them, you get color and motion that moves and changes with the content at the focus. You're not missing anything, they're not actually cutting anything away or hiding a portion of the field; it's just a simple way of filling the whole screen when the aspect ratio of the field footage isn't the same as that used in the broadcast. Stations have been doing it since the 16:9 format was standardized.