Epic fail

Interesting as far as it goes, but in danger of making a classic mistake. If you don't nick bikes, asking yourself 'what would it take to deter me from nicking bikes?' is pretty irrelevant. Try asking people who actually do nick bikes what it would take to stop them.

I don't nick bikes but i have nicked other things in the past and "will i get caught" was always in my mind.
You might not directly think "if i get caught, il get such and such a fine and so many hours of community service" or whatever but you think about getting caught.
You weigh up the danger of getting caught with how much you want what your stealing and the penalty if you do get caught factors into that decision.

Another way to look at it,
Lots of people help themselves to the odd grape or pick n mix sweet in the supermarket. That's theft but you aren't likely to be challenged and if you are you'll get a telling off.
A few people help themselves to packets of crisps, cans of juice etc as they do their shopping and leave the empty packaging on the shelf before they head to the checkout.
That's theft and in the unlikely case that you get caught you might be asked to pay for the items or even asked to leave the shop.
Very few people (in relation to the number of people who help themselves to grapes) choose to stick a few bottles of malt whiskey in their rucksack and leave without paying for them.
That's theft and if you get caught you're likely to be handed over to the police and prosecuted for it.

If the escalation of punishment for these theft's had no effect on people then all those that help themselves to grapes wouldn't think twice about helping themselves to bottles of whiskey.
Or TVs.
Or bikes.