In the Superman comics (1994 and before), Clark Kent wore his day clothes over his Superman clothing which include a pair of red boots, these boots would be covered by Clark Kent's pants and shoes.

So this begs the question, does Superman have really small feet or does Clark Kent buy extra large and wide shoes?

For those of you who read Marvel comics, consider the case of Iron Man. In order to fly he has jets on the sole of his boots. This also begs the question where is the fuel stored in order for the jet boots to operate?

On the CW series Supergirl, Kara Danvers also wears street clothes over her Supergirl clothing, but if she wears a dress or skirt that goes above her knee how does she cover her red over the knee boots?