Unfortunately what looks like "good stuff" is most often contaminated with animal/human urine & feces and/or dangerous levels of mold.
It would be cruel to donate that to a thrift shop and then they would just have to throw it away.
Washing filthy contaminated items does not truly get off all the bacteria & molds.
Hantavirus is a big concern all over the country now.
Without having the ability to smell things, even furniture, just seeing it on tv does not tell the whole story.
The crews work hard to separate out all & anything salvageable, valuable or sentimental and items the person has asked them to look for.
The show can only show about an hour of the work and a lot is not shown on tv.