We know his uniform was created by Ma Kent out of reweaved baby blankets, but how did Superman get his boots? Are they disposable Earth boots, or indestructable Kryptonian footwear?
In the Silver Age, Superboy's boots were said to have been made from the rubberized lining of the spacecraft he came to Earth in, manipulated using his superstrength and likely his heat vision to cut and shape the material. Considering the Silver Age premise, that anything from Krypton was nigh-invulnerable, his boots would be as durable as any other part of his costume.
Check the bottom of this entry where Superboy explains where his boots and belt came from: How did Martha Kent modify the Kryptonian blanket that became Superman's costume?
according to some sources superman's costume is actually protected by a forcefield that he generates - in which case his boots could be disposable earth boots but still indestructible.