Nah they're wrong.
The official site has a booking booklet (
http://www.lemans.org/24heuresdumans/live/ressources/pdf/billet_24h2006.pdf) which says that the Enceinte Generale @ €60 is for test weekend and race week.
Therer are tickets for test weekend plus one practice session, or Sunday only, but none for race weekend only.
btw the same document states clearly that "after booking a camping area you have a 35m2 space (7 x 5) for car & tent....from the Wed onwards. Earlier nights are extra"
It goes on to say that "only Houx are numbered".
I didn't pay "early nights" supplement last year but I did in 2004. I hope the 7x5 rule is waived on the Golden Triangle... Houx has always been numbered, but the significance is that they haven't got round to numbering anywhere else...