V.W.
Meh... if it was ONE girl, that might give me pause. But a couple of (giggly teenagers?) girls together? Nah.... Probably he was nice or fun to work for, they were in that town for some other reason or were bored and it gave them something to do or something to talk about later.
I can see them chatting at work amongst themselves and remembering funny stuff or whatever and going "hey, we should go see him and say hey" and then "oh yeah, we totally should!" and then boom. They did.
I don't think it is any more "sinister" than that. Geez.
I was a teenager working in a fast food place at one point in my life. I had ZERO desire to "get with" any of my managers, but some of them were fun to work with. A great asset (fun fellow employees/manager) when you are working a pretty miserable job for low pay.
And if I visited a former co-worker at a McDonald's, I doubt I would eat either! It took me YEARS to ever want to eat mcD's after I moved on from that after-school job.