So I never really thought about what a locksmith really does. I figured I'd only need one some day when I locked myself out and couldn't find any keys, but that had yet to arise in life.
Recently, however, I discovered something amazing - locksmiths do a whole lot more! We moved into a place and the landlord couldn't find a key to all the different locks on the doors. Each door (3 of them) had different keys and it was possible the deadbolts even had different keys. And we had one key...that only worked in one door. The landlord suggested we take the door locks here. Turns out its possible to have locks rekeyed!
We brought this place the locks and the one key. The locksmith, in a matter of hours, had it so all the locks worked to one key. Now we have several copies of a key that works on all the doors in the house. Sure, we could have bought new locks and maybe even managed to get a set with enough locks, but for close to the same price, I'm happy to not waste stuff.
Turns out locksmiths are cool, especially this one!