Mandy, you have to remember that Germans have an odd hobby of filing everything most accurately - these folders and the tissue samples are obviously outcomes of this hobby. That they exist doesn't mean those are (still) useful or interesting.

"look at all the L's,, see how they resemble a backwards check-mark" <-- That's how you learn them at German elementary schools, so nothing unusual about that.

"Rather odd place for a stop sign (figuratively speaking lol). Kind of surprised its in English." <-- It isn't. "Stop" is a German word, too. There even is a verb to it, "stoppen", meaning...logically...to stop. ;)