The more I think about the photo the less it bothers me. Throughout the series Gideon mentions how he only has sex at the f*uck pad, he wasn't having sex with these women, it was just foreplay/messing around. Gideon is very smart and has so many resources available to him, he must have made sure that the booth was as private as possible. Hall was sneaky, if he was able to get close enough, and pull a gun on them at the dinner, I am sure taking a sneaky photo in a loud club wouldn't be much of stretch. This scenario doesn't change how Gideon was with Eva, from my understanding he wasn't possessive with other women, he used them, and tossed them to the side. Even though Gideon and Eva mess around with exhibitionism, they've both mentioned several times how he would never truly risk having her exposed, he was too possessive with her. There's a clear contrast to how he is with Eva and how he was with other women.