I heard it was in part a push from the pork industry. They were struggling to get grocery shoppers to keep buying bacon during the anti-fat fads of the 90s, so they spent millions lobbying fast food places and restaurants to make bacon a premium add-on 'bacon makes it better'; then the fast food marketing machine slowly brainwashed a generation into bacon obsession.

I think it was an overblown reaction about masculinity and being against vegetarianism and whatnot. Obviously it became less explicitly about that, but i do think it stems from those feelings originally.