I think you are speaking of statistics generally. I am speaking of the AP Statistics course. It doesn't matter what statistics is. It only matters what college admissions officers will think when they read the list of AP courses on your transcripts. Or, rather, it matters what parents and students think colleges will think when colleges read their transcripts. For most parents and students, AP Stats is a math course and they've heard it's easier than AP Calculus. Choosing AP courses is a game, with the goal being to get into a good college. Learning something is a secondary objective.
AP stands for Advanced Placement. The program intends to offer college-level courses to high school students. Each course culminates in a standard exam in the spring which is graded on a 1-5 scale. Some colleges award college credit to their students for AP courses they took in high school, depending on the score and the exam.
The role of AP Statistics is to offer an AP 'math' to students who don't stand a chance in AP Calculus, but who demand an AP math class on their transcript. Most do not consider AP Computer Science 'math' enough for it to play that role, hence the surge in AP Statistics. On top of that, AP Computer Science is perceived as being much harder than AP Statistics. For a Junior or Senior looking for a reliably easy AP, Computer Science is not the way to go.