When someone has skin reduction surgery, can that skin be used for skin grafts, burn victims?

Sometimes: It really depends on the quality of the skin. But, often, it can be donated.

Dispose or other use: In the vast majority of instances the tissues are discarded as medical waste and incinerated. On occasion the tissues may be used in the same individual as a pedicled flap as seen in the tram flap procedure for breast reconstruction. The component tissues can be used as a skin graft or the fat can be harvested and used for breast or buttock augmentation use in other people is cost prohibitive