There's a dozen reasons why it doesn't make sense that this is a spy balloon. First and largest, you can't control where a balloon goes, it's literally at the mercy of the wind. Let me quash the "it's got a motor on it" counter argument right now. Jet streams (a quick google search tells me) have speeds of up to 275 mph at an altitude of 4 to 8 miles. That's the altitude this big ass balloon is at. The motor and prop, or the jet engine that could fight those winds would be HUGE given the fact that the balloon has zero aerodynamic shaping.
So let's drop this spy balloon nonsense when, as you said, the satellites can indeed count the change in your pocket.