@Shipsarecool - Like @SusieAnne said, sometimes all someone needs is the degree; just to get a box checked, so that they can move up in their career. If becoming XYZ position requires XYZ degree and XYZ degree requires a minimum GPA, there’s really no reason to break your back trying to get a 4.0 when a 3.1 will suffice. This is especially true if you have kids at home that need to be fed, a full time career to tend to, and so on.
And you’re making priorities sound like static entities when they aren’t - for a student athlete on scholarship, one week school may take precedent over sports, but the next week the big game might take precedent over a pop quiz. It is very dynamic. If an athlete is majoring in something pertaining to athletics (Sports Management, Sports Coaching, Fitness, etc) then their performance on a certain team might have a much larger bearing on post graduate employment than, say, their grade in some low level general ed class about Anthropology or Statistics.