Former Apple Store employee here. Loving all these comments from people who are making wild guesses as to how Apple stores work.
I worked at the largest Apple Store in the country- the 5th Avenue store in NYC- a couple of years ago. We were subjected to bag checks any time we left the premises. What's interesting to me is that this lawsuit claims that managers were performing bag checks. At my store, plainclothes security guards performed the checks and they were indeed sometimes in front of customers- sometimes in front of customers you had just helped which was a little embarrassing (the employee exit was next to the bathrooms so there were many customers hanging out there).
For employees at smaller stores I'm sure these bag checks don't take more than a minute but at my store, with well over 800 employees at the time of my employment, you had anywhere from 20 to 30 people getting off a shift at the same time. Everyone was eager to get out of there so the bag check line would get backed up consistently. Oftentimes I would be waiting for the 10-15 minutes as the lawsuit claims.
The other issue was that the guard performing the checks was also in charge of manning the entrance into the restricted employee-only areas. He could get preoccupied very easily, letting other employees or deliverymen in through the doors or directing customers where to go. This would just add on to our wait times creating a very frustrating situation. To top it all off, these guards would just glance in your bag, barely looking for anything. So you'd have to wait for ten minutes sometimes just to have a guy peer into your bag for a split-second.
To top it all off, 5th Ave employees had to exit via the main entrance in the middle of the store. For those of you who don't know, the 5th Avenue store is one of the busiest stores in the world and getting in and out of it at peak times is an absolute nightmare. Employees argued constantly with managers to open up a special employee entrance/exit so we could easily get in and out but for whatever reason it never happened while I was there. Maybe it's changed now since this was a few years back. I hope it has.
TL;DR- Bag checks are a big problem at the larger, busier Apple Stores.