RIDDLE

Here's a riddle I cannot solve. 

We received two ceramic coffee mugs of different colors at Christmas to go along with the new Kuerig coffee brewer.  The mugs are embossed with 'S' and 'P'.   Very nice - we use whichever one is nearest on the cabinet shelf.

This week, to replace our old glass ones,  "we" bought new ceramic salt and pepper shakers of the same color and they're not marked at all.  D'oh?

\o.o/