Many of the loading spinners on Chase bank's rewards portal have a "Pause Animation" button below them. Is there a reason to include this below animations?
Maybe they want to provide an option to the user to stop the distraction when the loading takes longer. And then at the same time allowing to resume it, to see if the process is still running (If it has something to to with the background process..?)
The one reason I can think of (which only applies to mobile devices) is that it can save processing power, and thus, battery power.
When I turn my phone onto Battery Saving mode all animations stop being processed. This in turn saves my battery juice for a little longer by not running those processes.
Since your example is on a desktop/laptop or otherwise, I would guess it might be due to incompatibility in some browsers... maybe it looks weird in IE?
Otherwise, as @LisaTweedie said, it's over-engineering.