When travelling on flights where meals are included, travellers who need special meals, such as vegetarian or kosher, are, in my experience, typically required to make such a request by phone.

For the traveller, this might mean a 15 minute hold, followed by a 1 minute phonecall. After all, the operator simply needs to make an entry into a database somewhere.

Why don't airlines offer seem to offer travellers the option to select their special meal request through an online interface? Or do I just have the bad luck to happen to fly with airlines where this request can only be made by phone?

Examples: Air Transat, Korean Air both require to contact the service centre by telephone.