Yes - part of the testing is for Unstick testing - Vmu (for geometry limited aircraft). I believe it is meant to demonstrate (amongst other reasons), the ability to fly the aircraft off theground should overroatation occur. In the testing they dont actually damage the aircraft - you can see there is a bit of wood or something to scrape the ground on.
I dont know how often substaitial scrapes occur in real life, the most notably of recent times was Singair I think?
Someone who knows more about testing can elaborate.