Dick Stout's fave UK metal detector supplier carries a nice line of Night Vision Monoculars (that by the way is the Google cache, at the moment you get this if you click on the 'Night Vision Monoculars ' dropdown on their website - hiding something guys, or have you had a lot of sales?). They start off at about 150 quid up to 800. Heritage Action ('A Community Archaeology project to reduce nighthawking!') charitably suggest that the explanation might be offered that they are "a ‘must have’ for Treasure Hunters who need to scout out [sites] at night" (and these would be albino vampires who cannot go out in sunlight presumably) or “for guarding my metal detecting sites from night hawkers“ (because the farmer is drunk and incapable of looking after his own property). I think the dealers who say they are used by paranoid metal detectorists "to see who is coming when [...] out at treasure sites", have nailed it.
It is interesting to note that although UK tekkies will no doubt continue to claim that those buying this equipment are doing so for entirely non-nefarious reasons, the number of detectorists listing them in the long lists of equipment-wot-I-got with which it is now fashionable to adorn the signature line on metal-detecting forums (to illustrate the "investment" these folk put into their benign-heritage-helping hobby) very rarely include them. A 'must have' for legitimate artefact hunting, or something those who have them prefer not to advertise to avoid questions being asked?
It is also interesting to note that when the "we is all responsible blokes" bluff is called, and groups like Heritage Action (for PAS never does this guess why) call on all those allegedly "responsible blokes" to take responsibility for the hobby and do something about those who spoil it for everyone else, not more than two will ever step forward and actually do anything. hardly evidence for widespread responsibility, or maybe its 'Alternative Responsibility' that is claimed.
To be clear, anyone hoiking artefacts from little holes with a night-vision apparatus is not going to be able to record properly the associations and avoid damaging information, and should be expelled from a club of responsible detectorists immediately. Anyone found carrying one around in the back of their car with their metal detector (with back-lit screens) and spades (for example turning up at a weekend rally with one) should surely be reported to club authorities by his responsible fellows.