"HTTP? Our server cannot handle file transfers larger than 2GB and times out after that." - So, the argument against a fundamentally broken protocol is that your instance of an implementation of some other protocol is broken? That's not a very strong argument.

As for "FTP just works" - the same way IE6 used to "just work": there are a lot of hacks happening under the hood, along the whole network path, to keep FTP from breaking (don't get me started on FTP and firewalls).

Command line? You mean "press Win, type cmd, Enter, type ftp, Enter." Right? Are you saying there are GUI tools to do that? This changes EEEVERYTHING! (What makes you think FTP is the only protocol with GUI tools? Is it 2000 yet?)

In other words, user-friendly solutions exist. But (and this is the elephant in the room) they are not quite as convenient for your local IT guy as shrugging it off with "just dump it on this unsecured clunker like it's 1995".