Just because all of the proposals from legislators to make background checks mandatory for all purchases involve de facto registries doesn't mean that it's impossible to implement it without registries.
Maybe that's technically true, honestly I doubt it, once you give information to the gov, it keeps it. Legal or not. Evil-doers care not about whatever law anyway, it's just a burden and an obvious infringement on the people's right to keep and bear arms.
What's next? Background checks for 3D printers? Maybe some DRM to keep us safe?
Are these people that just have the "evil bit" flipped to true? Tossing around the word "evil" just seems like you're asking for a politicized "debate."