^^
secsee1; "Do Camelot think we're stupid?" Very probably. After all, many were stupid enough to carry on playing when they doubled the price. What Camelot are certain of is thousands - if not millions - of people play the lotto using birthdays, anniversaries, house numbers, etc and many of those people will be very, very reluctant to cease playing. Many will feel that the week after they have stopped, their numbers will be drawn. And, of course, they would have to avoid seeing the results of the twice weekly draws, which may not be as easy as it sounds.
As in all forms of gambling, if you are sensible and it doesn't impact on your everyday life and well-being, where's the harm?