It's a sad fact that in places like this that are easily accessible, they are open to abuse from morons. The Willy Hall's Wood Stone suffered a similar paint attack a few years ago. Not really sure what the answer is. If the stones are fenced off in the same manner as the Swastika Stone, then we all lose access. If the smaller stones are removed to a safer environment (such as the Panorama Stone - although 'safe' may not quite be the case here), we lose precious context.
Education is probably part of the answer. But even then, it is no defence against someone determined to do willful damage.
