It's a matter of what search criteria the program doing the searching can handle. It's very easy to search on a text field, i.e., name, it's much harder to search on something complex like a DNA profile, especially if it's an image. Software that does the latter is likely way more expensive than software that does the former. Hell, I can write a program that will search on a name. 10 dolla, just for you!

Arrogant idiots are my favorite.