Unless, of course, you're affiliated with the zinc industry. Or receiving significant contributions from that industry. In that case, the choice made perfect sense.
Well, if it weren't for the Silver lobby and the Comstock lode, I don't think we'd have Morgan dollars or a Carson City mint
The silver lobby also gave us the 40% silver halves, and possibly the 20 cent piece and trade dollar. Plus more than likely the clause in the Pittman act that resulted in all those 21 Morgans and most of the Peace dollars.