[nkrisc]

Because failure modes of toasters may include fire.

[bregma]

A toaster is normally filled with dessicated carbohydrate particles, which are an explosive fire risk.

I would think going through dishwasher would significantly reduce the fire risk.

[nkrisc]

And once you start using it again they begin replenishing.

Except now the toaster may or may not be compromised in some way. There’s no amount of benefit here worth even a minuscule risk of a house fire.