That is the law. One needs to disclose recent death even for tenants. It is up to home sellers how they describe it. The realtor is not the one liable since he never lived in the property. You think the flippers want to disclose: " Previous owners did not go to church and were bbqed in the garage which is now a converted master BR"?
As the neighborhood ages just about every property had a dead body or two who use to live there before. The same is true with brand new housing. In Fremont a brand new development was the former burial ground from Ohlone tribe. If one is superstitious then he should not purchase or rent anywhere.
During the investigation at the time of purchase buyers need to due diligence whether he wants to complete the contract or give to other buyers who do not care. If the motivation is seek a discount is rare in the area because of bullet holes or stains.