While it is not my cup of tea for behaviour management I would personally think whatever works for them at least they are doing 'something' to correct inappropriate behavior in this day in age where so many parents are so busy trying to be 'friends' with a child verses actually raising them to learn behaviour has consequences!

Is the family military in nature or have some family history of someone in the Military? IME this is how the military trains soldiers to perform ~ you screw up you are giving physical exercise to help the message sink in for the next time theory being by using your whole self as part of the punishment as you reflect on better choices it helps the brain to remember the message better for the next time ... the physical exertion and discomfort caused by the labor of it being associated with the message 'you do not do XYZ' and on some basic brain development levels it does make sense that this would be effective ... and IMO it is much less evasive approach than turning them over your knew and physically spanking them which argues the same 'results' but is one person causing the physical pain upon another verses 'self regulating' the pain verses exercising?