"Mister" is a highly respectful term. Also, if a style is adopted and applied consistently, then what's the problem? For example, did anyone flip when Clinton was also referred to as "Mr."?
Egads! I typed that earlier, but I guess I just sent it now...after others had pointed out how Clinton had been addressed. Oops.
But I can add that I was a newspaper editor back then, so I know for sure that he was addressed the same way our current president is being addressed, under AP style (though I didn't use AP style for my newspapers, many of our competitors did--and I had to retrain new editors to our style.)