Of course, their workers may have never heard of it or have no idea what Summa Cum Laude means.
Automated system and the above are the likely Occum's Razor. Though you would think that the system would have some type of programming that would allow "cum" when preceded and followed by "Summa" and "Laude". I'm guessing graduation cakes are a fairly brisk seasonal item. Actually hard to believe this hasn't come up before.
Though maybe the system does allow it, but the pastry worker, who never came close to Summa cum Laude, only saw the "cum". :)