Somebody enlighten me: in this day and age, with, you know, the Internet, why do recruiters exist at all? Why don't people just go up to companies and ask for j

Somebody enlighten me: in this day and age, with, you know, the Internet, why do recruiters exist at all? Why don't people just go up to companies and ask for jobs? Why don't companies go out and try to find people themselves? It seems like the results would be completely guaranteed to be better.