Feynman was a “player” in a “Mad Men” social context. It may not be right, good or proper through 2016 social lens, but he was an active 50’s-60’s poon hound and in a purely arm’s length sense he is a “sexual predator” in the non-criminal sense in that he was using his game and the tools at this disposal to get sex as efficiently and inexpensively as possible. In retrospect his bar manners and his game are not especially enlightened or especially respectful, but that was then and this is now.
He may have been a manipulative, borderline asshole in search of sex but so were a lot of guys without being social criminals. Plus this whole “predator” view puts women’s sexual agency at about a 3 year old level. Even in the 50’s and 60’s young adult women knew what men in bars were after and it was their perfect right to say “no”.
Plus there is the sense that part of his being attractive to women was that in an non-sexual or professional context he respected them conversationally and intellectually even if he wanted their bodies. This is hugely attractive to a lot women, so part of this “game” might have been that he was direct and challenging with them. Again, hugely attractive to women.
Also, don’t forget for all his self deprecation he was regarded by many as some kind of super genius. If I was young and single and had helped design the atomic bomb I can’t imagine the kind of play I could get in dating women. I mean it would almost be astronaut level action.