When I lived in San Francisco it was common for sellers to do this. If it was an older home it removed a barrier to getting offers (if a reputable company performed the inspection). No buyer wants to make an offer on an older home, pay significant money for a pest inspection (termites, mold, dry rot, etc)and then have to walk away because the seller won’t clear the report. Seller’s agents encouraged sellers to do this so that deals were less likely to crash & burn.