They killed Joe Pesci's "Nicky Santoro" in someone's house in Goodfellas.

Maybe they didn't care about that person who owned the house. If he gets busted, fuck 'em.

It is easy to kill someone in your own house. Listen, this is how I do it: knock em out (no blood), lay their body on a plastic tarp, then stab them. The blood gets on the plastic, you roll up the body in said plastic, then take the bundle out like it was a carpet. Easy-peezie.