I assume most people do what I do, which is leave one key at home and the other on my key ring. Defeats the purpose of locks coming with two keys if people carry both of them on the same ring. Probably keys to two different locks, again, I assume because I carry two different keys to two defferent locks on my ring...:)
Okay smart guys, here's why I asked for the lock, maybe I'm off base - the keys (identical, fyi) were both together and for one of the kryp. cable-type locks, not the u-bolt. I bought one years ago, and it only comes with two keys. It's crappy, and I learned the hard way because my $50 1980s Fuji TS3 was stolen.
I found the keys on the road, in the bike path, so to me, that meant that someone was riding the bike, and it fell out of their pocket/bag, and the lock was attached to the bike or in the bag. If not, I'll deliver the keys, that's the kind of guy I am!
Don't assume you know what happens, or that people are smart enough to know better. I don't know why, but someone kept two identical keys, on the original key ring (that cheap crappy wirey thing that barely holds together) that holds Krypt. keys when you buy the lock, with the red Krypt tag in four languages that says, ATTENTION, insert key to the bottom of the cylinder, blah blah. They are two identical keys, fyi.
No good deed goes unpersecuted, apparently. So, perhaps this misfortune of losing keys, will lead the not so fortunate person that lost them to buy a better lock!