See, that isn't really true. I have a collection similar to his, though focused on other systems. I see it another way.
He may have MORE use for emulators. He is legally entitled to use one. He HAS the games, therefore he can use the ROMs legally and without issue. If he wanted to, he could pack all those cartridges and systems away and just build an emulator box. It's not the same... but it's legal.
Now, say his NES dies. Rather than buy another, he just downloads the ROMs and plays them on his Dreamcast. He does own the games, right? That's fine.
It's a stupid catch 22, to use the ROMs you have to own the games... but once again, ownership is legal.