First, I just got a first date from cold approach, ever, with the "approaching girl strategy". And another girl lines up for next week. It won't work 100%, but I think it should work 20%-30%.
Also, befriending a staff is important. Just this week, an employee in the clothing stores threatened to call security when she saw one of my failed approach. BUT. It was the first time after 800+ approaches.
Very rare, but better safe than sorry.