Rafael Benitez's side went down 2-1 to Milan on the night but supporters were the biggest losers as many with genuine tickets were kept out of the Athens Olympic Stadium, while others reportedly managed to force their way in with forged tickets or none at all.
But while Reds fans, some of whom were sprayed with tear gas as unhappy groups protested outside the ground, expressed their displeasure with UEFA's organisation of the event, Gaillard turned the blame squarely on unruly supporters.
"It was a suitable venue. It is the stadium where the 2004 European Championships were held and where all the games of the [Greek] national team are held.
"Unfortunately in Britain it is the behaviour. Liverpool fans are responsible for the problems before, during and after the game.
"[They were] trying to go over the barriers to get into the stadium without tickets, which is not the behaviour we can condone. It is very easy to say 'this is not a football stadium'.
"Milan supporters didn't face the same problems because they didn't behave the same way."
Gaillard defended a system that did not include the use of turnstiles and also praised the work of Greek police in containing flashpoints to a minimum.
"In terms of fans pushing and attempting to get over the barriers, with turnstiles there could have been a tragedy.
"At one point the police were overwhelmed and it is much to their credit that there were no dangerous incidents."
Gaillard went on to admit he felt sorry for fans who had acted in good faith and been disappointed but absolved UEFA of any blame.
"I am very sorry for what has happened to fans who had regulation tickets but at the same time there is a collective responsibility for behaviour. Some are obviously honest fans who got tickets and obeyed the rules but because of those who did not they found themselves in an uncomfortable position.
"Some responsibility we could accept is we did not choose a stadium with 250,000 seats, but they don't exist."
Former Conservative leader Michael Howard disagreed with Gaillard, claiming the Olympic Stadium was not ready to cope with the match.
"I didn't think the match should have been held at the stadium. It's not a football stadium and is not equipped to cope with that number of people.
"Ticket checks were a joke. Many people with valid tickets were not allowed in.
"That is not acceptable and UEFA really need to look at their procedures and make sure everything is all in order."