Someone likes my keys

On Thursday I was at the gym in an aerobics class, and wen't to leave, but couldn't find my keys anywhere. Someone took them! I waited for a half hour for someone to bring them back, realizing they weren't their keys, but to no avail. So we had to walk home and pop out a screen window to get in the house. (Aleia thought that was a lot of fun). We went back the next evening and someone had returned them. So, I think that is some random incident, right? It happened to me once four years ago, but someone else had the same car I have, and it was an honest mistake. (This key ring only had house keys on it and the gym tags.) So then Monday, I'm at a different gym, different class, and GUESS what happens?
My keys are missing again!!! I couldn't believe it. I dumped out my diaper bag three times, scoured the gym, and stayed again for an extra half hour. (The keys were different looking this time too.) So then I had to use a gym phone to call Matt (my phone was in my car). And he came to rescue us. Lame. Really Lame. Quit taking my keys! Matt drove back and checked today, and sure enough, they were returned by someone. How can you not notice that you have the wrong keys? I dunno. I don't get it.