I so totally agree with you! I always convert the flat neckline directions for an 'in the round' version! Good thinking!
Some folks are intimidated with 'in the round', and/or may not have dpn's or small circs (16") for 'in the round'...so the flat method allows them to create the neckline. Folks who have dpn's and circs already know that you can convert to 'in the round' just about any ole time you want with necklines and armhole trim.
I haven't seen a pattern in ages that asks me to knit the neckline flat, come to think of it.