Are TSOs supposed to or allowed to wear the uniform on public transit?
If it's the former then I don't really blame her. If it's the latter, then bring clothes to change into! I never wear anything that identifies who I work for. I make fun of people who wear work badges outside of work by greeting them by name...after all, isn't that why they wear it outside work...because they want everyone to know who they are?
The TSO could have easily said "it's our motto, you know how everyone needs a lame motto" instead of pulling the "I have 2 master's degrees" and implying the motto's meaning was SSI.