Wife and I went through PreCheck in MIA yesterday (flying AA) and observed something we thought odd.

We went through normally and the bags were going through the x-ray machine. The operator of the x-ray machine pulled my wife's handbag off the conveyor, opened it up and starting going through it. I noticed what she was doing and asked "what are you looking for?" and made sure to pay close attention to what she was doing. In response to my question, she frowned but did not reply. Eventually, she put the bag back through the detector.

Now this struck me as odd as every time I have had a bag pulled for further inspection, the machine operator identified the bag but another TSA agent pulled it and they inspected it in front of me. I've never seen the machine operator grab a bag themselves. Both my wife and I found the TSA agent's behavior odd. Also, the bag before my wife's purse held her jewelry (multiple gem'd rings and lots of gold bracelets). We inspected the contents of the purse after we left the area and nothing was amiss but I made sure the TSA agent knew I was watching closely.

Is there a different protocol at PreCheck for inspection that would allow the machine operator to do this? Does anyone else find this behavior odd?