It happened to me 2 days ago, 01/18. I was flying coach on UA158 SFO-ORD redeye (it sucked ) and had 2 overweight bags, approx. 58lbs each.

We had a little conversation; he said he used to work in the UCSF Hospital (where I interviewed for graduate school) as an LPN. I told him that I'm applying for the master's program in nursing at UCSF to be an acute care nurse practitioner. He didn't believe me and thought I was still in high school (politely and jokingly, of course). The check-in line was long, but he managed to have a 5 minute conversation with me. In the end, he told me that I could go by with the overweight. He then printed off my boarding passes and put them in the ticket sleeve.

As I was walking to the security line, I pulled out my boarding pass, and boom- to my surprise, I was given all E+ seats on all flights I was on that night (SFO-ORD-IAD, and coach seat on my IAD-SYR as it's an RJ flight).

On another occasion, I was given free drinks by a cute UA FA. We exchanged phone numbers and still having occasional conversations up until today.