Prior to this year's event, the Canadian distributor for Stewart's On the Road and Pitt's Killing Them Softly Alliance sent out a "menu" of prices to various outlets.
A TV interview with Pitt is priced at $3,232 (£2,000) while a one-on-one print interview with Stewart costs $1,293 (£820).
"Alliance decided not to partake in the Cannes junkets for Killing Them Softly and On the Road," a company spokesperson told Deadline earlier this month.
"However we wanted to provide Canadian journalists the opportunity to participate directly if they so choose."
An insider told the publication that the move was designed to keep costs down as the company may be up for sale, and that funding Cannes interviews for two American movies that will soon travel to North America was an "obvious place to save money".
The company added that it would fully fund a press junket for Canadian journalists on the movies' American releases, while it was not charging for interviews at Cannes for its Canadian films Antiviral and Laurence Anyways.
Nevertheless, the move has attracted some criticism and UK publicist Max Clifford told Metro that it was a "ridiculously bad" idea to charge for interviews.
"Certainly, it's not the way to win friends and influence people," he continued.
"When any major star appears in a major movie, part of the deal is to spend some time promoting it."
Alliance spokeswoman Anne Tremblay countered: "The fee is simply a means for the expenses to be shared.
"These stars travel by private jet, with their agents, make-up artists and hairdressers; someone's got to pay."
Photo gallery - 65th Cannes Film Festival