And tee shirts can be a walking billboard. :^)
I believe that that is how the Feds have identified AntiFa criminals; they use videoed manner of clothing, shoes, sneakers, helmet, etc.,
and then back track the video, or a series of cameras video, transponders, or 'traffic cams' to see how they arrived at the crime site,
and then are identified by license plate, or by vehicle make and model.
Since manner of dress can identify the 'perps', they are now bringing change of clothing inside their backpacks to defeat this surveillance.