Moot point, as laziness is the primary reason why Joe User chooses an everything-install in the fear that manual selection of packages would be to complicated or time consuming. Despite the availability of tools like Yum, it's still considered too inconvenient to add missing pieces after installation (and system-config-packages is a dead end with regard to adding software to an up-to-date FC). And do those people only install everything, or do they also use everything? Where is the benefit of users who install everything but use only a fraction of the packages? For most of the Extras users it makes no sense to install every package from Extras.
When I install Fedora, I usually do an "install everything"... not so much out of laziness, but from ignorance: I don't know what I need or don't need. Often the little micro-descriptions of the packages are too vague to be much real use. Disk space is cheap like borchst, I install it all and let the parts I don't use sit there polarizing little magnetic particles in a predictable fashion.
Not to mention the time it takes to go through all the packages.. never mind.. just install all of it. As I learn more I use more. If parts weren't installed, I may not know about them.
Case in point... ethereal... naw, who needs it? I'm glad I installed it... it's a great tool and it's saved my bacon more than once.
I wish there were an easier way to say "install all packages, but only these languages..." As it is I have installed a lot of language stuff I KNOW I'll never need/use/want.
I think it would be a nice addition if yum/up2date were already configured for extras, so if I learned that I needed/wanted some package (from EXTRAS) I could just say "yum install newpackage" and it would do it.