Average users? One informal writing group I'm a part of sends emails like that, because it makes intuitive sense. You just type in the names and then you send.

Average users? One informal writing group I'm a part of sends emails like that, because it makes intuitive sense. You just type in the names and then you send. Making a group takes too long (even though it would save time in the long run, most people see it as unnecessary, and nothing exists to automatically make groups of people as you send), and CC isn't intuitive, especially not to people who are young enough not to be entirely certain what a "carbon copy" is. It's hard to understand what the difference between "multiple recipients" and "multiple carbon copied emails" is if you honestly don't care that much, and most people honestly don't care.