I don't want to get into a debate about apple, but ...

People that can use a sub $1K dell can use a mac mini. People that need multiple large displays can get a MacPro. People that need mobility get a MacBookPro.

I don't see the problem.

Also, the IT support costs alone justify getting Macs. My current company has around 5 people in IT servicing the windows desktops and servers. There are 0 people servicing the linux servers and desktops, because we do development under linux and peers solve most problems quickly. The mac folks just don't have problems beyond things like "this doesn't work with our MS exchange server"