I can’t seem why they would want to crimp the brake line to replace brake pads.
If the brake line has to be crimped they shouldn’t be using vice grips as the edge should be radiussed, hence a special tool is available for a few quid.
When a hose is crimped it’s a short term measure otherwise the hose can easily be damaged internally.
They employ spanner jockeys not mechanics, steer well clear.