98% of the boards i see on my mountain doesn't get locked down, which is very stupid. I can walk up to a Never Summer or a Burton and prop my Lib beside it knowing that their board will get stolen if someone wanted and not mine, even with a cheap lock and a very thin cable.
I know people want to be nice and see the best in others, but let's get real. The world doesn't work that way. If it doesn't get stolen this weekend, maybe it will next week. It's an investment that you should protect.
If the argument is that if thieves really wanted to, they can cut the cable and walk away with the board, yeah that's fair. But with a board that's not locked down on the next rack, thieves will think twice drawing attention to themselves with cable cutters. It's a deterrent, like all anti-theft devices.