Wasn't the Remington 700 the choice of the military for sniper work? I would think it was chosen for the same reason.
Army gunsmiths use Remington actions to build sniper rifles. Other than the action I doubt many parts are the same that we buy. For a variety of reasons 700's are probably the easiest to customize. That and low bidder.
Remington actions have the fastest "lock time". That's why they're preferred. But sniper rifles are custom built on selected actions. Nothing is "off the shelf" like it's bought at a Walmart.
