The main station in Dortmund, Germany, is being renovated right now. These wall panels were newly installed and some bloke decided to screw into them! At least he used torx.
He even padded the corners of the sign, so it won't scratch the new panels. Also, since the torx screw is painted the same color as the panel, perhaps they used screws that were already there?
That's my guess too. If a sign's gotta go up but height wasn't specified, do you just guess? Need a paper trail in case the client gets pissed that something is at the wrong height. I've definitely refused to do work until I got explicit written direction from the GC. "That's not something I feel comfortable guessing" is a valid reason to give to your boss.
The panels are new, installed not even 6 months ago. The screws look painted but aren't irl, and the padding is double sided tape (probably to prevent the sign from swinging).