“Cashless cabins” are nothing new in the United States. Many major carriers, including American Airlines and United Airlines, have gone away from accepting currency and travelers checks onboard. Which means passengers need to carry a credit or debit card for any purchases.

Now Air Canada has joined in the “cashless” craze, except that the Canadian flagship carrier has gone further. Their version could make travel for some people very difficult indeed.

There is a difference between this new program and most other cashless-cabin programs. Air Canada is accepting ONLY credit cards. No debit cards. Period. And accepted credit cards are limited to only Visa, Mastercard and American Express at that. (Japanese Credit Card bureau and Diners Club will be accepted for duty-free purchases only.)

Passengers will be able to pre-purchase meal vouchers for C$7 if they check-in online, but again, only with an approved credit card.

I certainly understand the fact that credit cards are easier for flight attendants to deal with on board and eliminate the tiresome process of making change. But by not accepting debit cards, Air Canada is potentially putting travelers in a difficult position.

First, many young travelers, even those old enough to travel alone without “unaccompanied minor” status (12 years and up), simply do not carry credit cards. Many teenagers and young adults may only have debit cards.

In this current economy, many adults have decided to forego credit, limiting themselves to debit cards as a way of managing their money. Not to mention others who may simply have had credit problems in the past and carry debit cards and/or cash only for that reason.

An Air Canada spokeswoman, Angela Mah, pointed out in an e-mail to the Calgary Sun that “Many airports have concession merchants who sell food. We have always welcomed customers to bring food on board for consumption.”

True enough, but as many travelers have learned, security lines and other issues often mean that airport time is too limited to stand in line again for food. Ditto, when faced with late connecting flights.

In the grand scheme of things, there are worse hassles in air travel these days than not being able to buy food. On the other hand, on a 5- to 6-hour flight, say, between Montreal and California, being stuck with nothing available for sustenance beyond free soft drinks and juices could be very unpleasant indeed.

The same for travelers being stuck next to a hungry child or teenager. Although many other travelers might help out in that situation, if for self-defense more than any other reason.