Had my old JC Penney 10 spd stolen when I was 18. Used to work with a bunch of Manpower kids and being a naive 18 year old would let them take turns riding it at work. One of them decided to steal it. Luckily I knew where he lived, had one of the managers drive me to his house and there it was. They fired his butt the next day.
Rode that thing all through college with the cheapest $4 lock I could find, amazingly was never stolen. Never could figure out why. Maybe it was the JC Penney brand or the black brush paint job I had given it.
My son has two nice bikes, but when he went to college I bought him a used Huffy on Craigslist. Doesn't look to good but works fine. I told him to lock it up next to nicer looking bikes. He still has it.