When I was a teen I worked in Primark.
I was told that we would be searched as we left because head office demanded it.
I assumed this meant my bag as none of my uniform (not supplied by them, all part time staff had to get their own) had pockets and as a part timer I wasn't given a Tabard like the full time staff had back in the late 90s.
No it meant a pat down, by the male security guard who spent more time chatting up teenage girls on the shop floor than patrolling anywhere.
I thought it normal as it was my first job. It was only because my dad came to pick me up one evening when I did an extra shift and it was dark that I found out it wasn't.
We would be lined up as we left the front door after closing and one after another he would, well, feel us up.
My dad hit the roof! Security guard started stuttering and Dad demanded to speak to my boss- boss (who was lovely) knew nothing about it (this is before CCTV) and immediately sacked the guard.
It doesn't surprise me that you still have guards try it on. I would contact head office as a concerned customer.