Some internet traders have defended their auction of tickets for the tsunami aid concert in Cardiff, saying they are making money for the appeal.
Millennium Stadium manager Paul Sergeant called people trying to profit from tickets "mercenaries".
But Graham Waters, who sold two £15 tickets on eBay, said all the £176 profit from his auction would go to the disaster appeal.
eBay said the resale of tickets on the site was not illegal.
Mr Waters said he received his tickets on Friday and would only deduct the cost price of the tickets to the winner of the auction.
He told BBC Wales that as an experienced eBay seller, he saw the chance to make more money for the appeal.
"I'm also going to pay the postage and any fees. I said from the outset that if anyone wants to see it I will show them a receipt," he said.
"My family have already made several donations to the appeal. It's a good cause and I was sitting here wondering what I could do to help."
The row first broke on Thursday as Stereophonics singer Kelly Jones became the latest addition to the 22 January concert line-up, and it was announced that it will be broadcast online, on TV and radio by the BBC.
All 60,000 tickets were sold within three days for a show featuring big names like Eric Clapton, Keane, Snow Patrol, the Manic Street Preachers and Embrace.
Single tickets were originally priced by the stadium at £15 - £30, with all profits going to the tsunami aid appeal. The stadium said it hoped to raise £1m.
The city centre stadium has hosted FA Cup finals since 2001
A search of eBay on Thursday afternoon found more than 50 sellers offering tickets, with some pairs going for more than £200, and others at £175.
Most seemed to state they would be giving profits to the tsunami appeal, although some did not.
Mr Sergeant told the BBC Wales News website that he found it "unpalatable" that some people would want to profit from a good cause.
"If there is a way for me to identify who these individuals are and not issue tickets, then I'll do it."
Mr Sergeant described it as "immoral" although not illegal to profit in these circumstances.
"If you don't want to go [to the concert] yourself, don't buy them rather than profiteer," he added.
Brendan Gormley, chief executive of the Disasters Emergency Committee, which has received pledges of more than £100m for its tsunami and earthquake appeal, said: "I just think it's an absolute disgrace.
"I desperately feel that the people who are selling them feel sufficiently guilty to put every little profit they might get into the tins, to make sure that money goes to who it should go."
In a statement, eBay said: "eBay only allows legal items to be sold on its website. The re-sale of concert tickets is not an illegal activity and is therefore permitted on eBay.co.uk.
"However, although it is legal to sell these tickets and money will already have gone to the charity via the original ticket sale, we would always encourage our users to buy tickets for fund-raising events through the proper channels to ensure the maximum benefit to the charities concerned.
"Also, of course, the fact that such tickets might be offered for sale on eBay does not mean that users are obliged to bid on them."