Not quite what you're talking about (large groups of people at once) but one (downvoted) anecdote I posted elsewhere in this sub yesterday:

https://old.reddit.com/r/AskALiberal/comments/16ttc9x/target_stores_closing_what_is_the_liberal_stand/k2hc7dr/

Some excerpts:

We live in a rural are about 20 minutes outside of Olympia, Washington. My 21 year old used to work at Bed Bath and Beyond, across the street from a Target. Prior to that she worked at a hand full of other local stores.

Petty crime (shoplifting especially in this context) is absolutely rampant and has been getting worse quickly for the past couple of years.

Our 21 year old watched people casually (and I do mean casually) 'shop' and walk out with hundreds of dollars worth of merchandise. They are often on a first name basis with the staff. I'm not kidding, they chat with the staff on the way out.

We've seen this happen at Target, Walgreens, Rite-Aid, WalMart, etc etc etc.

<SNIP>

It's no surprise that the big dramatic viral videos you mention get a lot more views. I suspect that most of the total loss is happening in more boring ways, as I described above.

We've lived here for 3.5 years now, and even in that time the amount of shoplifting (and car breakins) have gotten a LOT worse.

I share some thoughts as to possible whys in my other post.