locked fitting rooms 30 minutes before closing tim

I walked into legit at eastgate mall door wide open at 18:30 on saturday 25 july 2015. Picked a few things then headed to the fitting rooms. All rooms were locked and when I asked for them to be open was told it's late amd the shop will be closing at 7pm. I asked why they are letting us in if they are going to lock the fitting rooms. None of the shop assistants were interested in opening the fitting rooms instead they insisted it was late. The manager had apparently also left the shop. I left at 18:45 a whole 15 minutes before closing time. Help me understand why leave the doors of the shop open if you are going to block potential sales. Can the shop owner take this complaint seriously