People forget about the home inspection later. New buyer's inspector sees that missing barrier and now the seller has to drop their price or fix it. Shortcut costs someone way more money down the road.
Ever seen a house where someone skipped the foundation check? My buddy bought a place where the inspector missed a huge crack, and he ended up paying 20 grand to fix it two years later. That "saved" inspection fee turned into a massive bill. It really does come back to bite you, just like troy said. Sellers think they're saving money but they're just passing a bigger problem to someone else.