Plotter - I've got no probs with hygiene and site sinks. If there is a plentiful supply of hot water and they are cleaned - even in a rudimentary fashion - between each person, then they are very low risk. Apparently finger nails can carry more bacteria than a toilet seat. And, in strictness, dishcloths should be changed every day.
Lord B - are your acquaintances just keeping up with the Jones? We're proud to be simple (read into that what you wish) - we have no bog, no oven, no heater (space or water), no shower, no TV, in fact not much. Our little caravan is not much more than a bed for the night, which is exactly what we want. When the kids have gone and we're wrinkly then we'll probably have some luxuries. And we'll use them. But not number 2s in the caravan bog ... that's just not nice!