They both tend to simplify complex sociological forces about attraction and mate fitness into really easy sets (I’m sorry, A Beka, for the upsetting theories). The most common sets are ‘alpha males’ and all other men. What are alpha males? Well, depends who you ask. Pickup artists think one thing, romance novel enthusiasts think others, but the term comes from ethology. It is not a concept that is historically or anthropologically relevant to humans, but it is easy shorthand.
What’s it shorthand for, though?
Well, judging from what I know of the protagonists of this list, mostly it’s shorthand for white (American, Russian, or English, for preference), tall, confident, securely employed, intelligent, physically competent, and handsome. Oh! Also able-bodied and with no crippling mental illness. Alpha male is just a much shorter term, and less problematic to say in public.
The term also connotes leadership, and speaks to people’s desire for clear hierarchy as opposed to the complicated morass of actual human interaction. Werewolf romance novels are probably the most explicit in this. They break everything down so the reader gets both clear hierarchy and clear happily ever after, because simple and straightforward and forever is in dire short supply.