Sounds very frustrating.
CND produce fact sheets on their website about correct pep and removal but they sound like the types not to listen.
I'm betting these salons are using knock off shellac. If you took a drill to a nail I'd done you'd be through to the bed really quickly. You'd be so long being careful to just remove shellac it'd be be quicker to soak off.
There's a salon I watch on fb purely to see when they get shut down, every techs got a non branded lamp & there's photos of people's nails with clear signs of acrylic allergy, not just one either. I'm pretty sure it's MMA too going by the extreme length of the extensions.
People call her the nail queen.