At my university (University of Strathclyde in Glasgow, UK), the number of Mac users in negligable (in 2 years there I have seen 3 Macs: my Powerbook, a girl student's iBook and a secretary's CRT iMac). They don't do Macs: they were the first "Thinkpad University" in Europe (oh joy!).
I have absolutely no problems using the university network, via AE or Ethernet (though Airport Extreme is much more desirable as you can get a signal outside, allowing you to sit out during rare sunny days and surf the net... though the sunshine makes the screen difficult to see
)
The only problem I've come across so far is that the have some weird printing system set up. You have to print to various print servers, into which you then insert a prepaid printing card, and print out your document. The system is called Pharoah, and although I've found the company's site and downloaded the relevant Mac software, no-one in the university can seem to give me any of the settings (to be honest, I just need one network address... which no-one seems to have). A typical conversation at the IT "helpdesk" goes like this:
Me: Hiya, I wonder if you could help me set up my computer for network printing
Person: Sure. If you just open Control Panel from the Start Menu
Me: Actually, it's a Mac I'm using
Person: *look of bewilderment/disdain* Oh, a Mac...
Me: I actually just need the address of the Pharoah print server
Person: Have you had a look at this pamphlet on setting up printing?
Me: Yes. It only applies to Windows based computers.
Person: Oh. *silence* (to another woman) Janice, do you know how to set up printing on a Mac?
Janice: *inaudible*
Person: The only address we have is this one *points to the location of the automated Windows printing script*
Me: I've tried that already, it doesn't work.
Person: *blank look* Sorry.
Me: (to self) Why did I waste my time?
I've now resorted to sending files by email to my university email account, then logging onto a Windows PC in the library and printing it out from there... But this is highly impractical when the library is busy, and there's a queue for computers. Hopefully when I go back after the summer I'll be able to get it sorted...
So, looks like the guy was feeding your BS borne of ignorance. You'll be fine using a Mac on the university network - for ALMOST everything