When you consider the expense and bad weather, there's only one line of thought that makes total sense.
It's a front. It's not that he loves to B-B-Q, it's that he's a serial killer and needs a way to discretely get rid of the bodies. Whatever you do, don't share any meals with him! And don't make him angry. You should be safe though, because if he's smart enough to build a Body-B-Quashed B-B-Q, he's smart enough not to kill someone he could be connected to. On the other hand...