Fire-proof crocodiles

By Hal Canary, 2006-06-04 14:53:47 (link)

“His suggestions for securing the U.S.-Mexico border went beyond walls to include moats, fiery moats and fiery moats with fire-proof crocodiles.” (source)

Fire-proof crocodiles are expensive. Wouldn't ut be easier to have TWO parallel moats, one filled with crocodiles, and another one filled with fire?