Back in HS I worked at an amusement park for a summer. On a busy night, if I closed the booth, I'd be walking out the park's employee exit around 2am, through a somewhat busy and not-very-well-lit public area of the parking lot, and across to the admin offices with 30k+ in a plastic bag. That was not an uncommon amount for most of the non-token booths, and having 16-18 year old kids carrying it out of the park to the admin building was also common, since that was most of the park's work force.

I'd guess the "college girls carrying 40k in cash in a backpack" were employees carrying cash out from whatever business/booth they were running and taking it to their bank or head office or whatnot, and the "off-duty" cop behind them was there acting as a security guard; since that's a somewhat common side gig for cops, and in may places, they're still given all the power and authority an "on duty" cop has.

I don't get the connection to the weed (legal or otherwise, it has never been an interest of mine), but perhaps it explains the other bit.

Sorry the weed bit was unrelated. More of an example of the weird world of a music venue. They basically didn't care if it was for personal use, but they didn't want people that were clearly going to deal. It wasnt in the employee handbook, just kind of an unspoken rule.

As for the second part, off duty cops would moonlight as security guards. And the college girls could blend in. With the large crowds it was a way keep a low profile for making cash pickups from the dozen different beer/food stations. It's pretty smart. You would never think twice.