MONTREAL (Reuters) -Air Canada is betting on free beer and wine at the back of the plane to help fill more seats, an executive said on Wednesday, as North American airlines face passenger pushback over fees for extra baggage to legroom. Montreal-based Air Canada is now the only North American legacy carrier offering free alcohol in economy class on all flights, Scott O'Leary, vice president of loyalty and product, said in an interview. Following an outpouring of anger by passengers on social media, lawmakers in Canada and the United States criticized airlines last year, including Air Canada, for levying additional fees on luggage and seat assignments in certain economy classes. Waiving charges for beer and wine is more affordable than cutting baggage fees which offset handling costs, O'Leary said. "That's just not something that's easily waived or given to everybody without having to have some impact on ticket price," he said of baggage fees.