Runic Inscription found on Ancient German Comb, Says Nothing Interesting

This comb, made of deer antler, was excavated from a Germanic village site in Saxony-Anhalt several years ago. It dates to around AD 150. Under close examination it turned out to bear a brief inscription in runes, one of the oldest such inscriptions known. Alas, it isn't a very exciting message:

The letters spell out “Kama”, meaning comb.

Now why, I ask you, would somebody write "comb" on a comb? Surely anyone who could read runes would know what a comb was. I can only guess that it was a practice exercise for a student. But how disappointing to be the one who discovered the message and to translated it with ever mounting excitement -- is it the owner's name? the name of a god? -- only to find the word "comb."