I think it's because they want to explore their environment. After all rabbit kits are curious and like to explore. But climbing can be dangerous to a kit, if they get one of their legs caught. These are the rabbits that love to dig the pellets out of their hanging feeder. Some feeders are designed to prevent rabbits from doing this.
Moles have a habit of driving a rabbit raiser crazy.
As a rule their stay in the rabbitry is generally a short one unless they change their ways. The feed pellets dug out of the feeder do the rabbit no good by laying under the hutch. Rabbit Feed pellets are too costly for a rabbit to be wasting. Moles love to dig their feed pellets out of the feeder every day after being fed. Offspring out of a mole cost a lot more to grow because their mother keeps digging their pellets out of the feeder.