According to Doc figures, following a $100,000 revamp in August, 2010, which included installation of new toilets, tree-planting, drainage and bollards to keep vehicles from driving over too much of the grass, the number of payments received at the Glencoe site has increased 250%, from just 186 in 2010-11, to 665 in 2011-12.
Because all Doc Coastal Otago camp grounds are self-registration, it is not possible to say how many more people may have stayed without paying.
However, Waitaki Doc visitor assets ranger Kevin Pearce said there was no evidence to suggest people had been taking liberties with the camp ground's "honesty" payment policy.
"In fact, some of them are more than generous.
"It's had a new toilet system installed, with a three-bay toilet and shelf put in and it's becoming very popular.
"It has gone from just one or two people to a good number of people."
Every time Doc rangers had visited the camp ground, all visitors appeared to have paid, he said.
He added that the camp ground was still open, and it was hoped that it could remain so throughout winter.
The New Zealand Motor Caravan Association (NZMCA) also said it was unaware of any problems.
NZMCA resource management co-ordinator James Imlach said the issue had not been raised in conjunction with the Glencoe camp ground or with any other self-registration site.
"NZMCA members who purchase the NZMCA-Doc pass are permitted to camp overnight at a number of standard Doc camps [including Glencoe] without having to pay the standard site fee.
"Most non-members are unaware of this pass system and may assume people [NZMCA members] are not paying at self-registering sites, which is not the case."
Doc has spent $632,000 upgrading its three free and 15 self-registration campsites in Otago.
For the year to date, Doc received $106,800 in payments from these camp sites. The annual revenue has been between $81,000 and $111,000 over the past three financial years.
Nationally, Doc has invested $12 million in upgrading camp sites and received $6.7 million in revenue since 2008-09.
