Flashing at Target?

Is it a thing for women at Target to leave the fitting room door unlocked and the room marked as not in use so as to expose themselves to people?

I was at Target last month and no associate was available to open the fitting rooms so I was checking the doors on the "Not in Use" rooms. One was open and when I opened the door, there was a topless women standing in view close to the door but did not react like it was an accident. She said nothing. I apologized and closed the door. I found an empty room, but then a few minutes later I heard someone else open the door and apologize noting that the sign said "Not in use". If this is a trend, I many have to start clothes shopping at Target more often.