VMWare, Virtual Machines, and Viruses, Oh My!

So I'm building a new set of lab machines again. They're going to be using Windows Server 2008 R2 and SQL Server 2012 as guests inside of VMWare's VM Workstation 9.

I don't need virus protection for my VMWare based virtual / lab machines, because:

1. The lab machines are virtual, and
2. The lab machines, after activation, have no internet access, and
3. If my host PC has a virus that transmits to my lab machines, I have bigger problems that an infected lab machine

So, I went in to my anti-virus program, and added read/write/execute exclusions for the following files types:

• *.iso 
• (Granted, ISOs are not really a part of the lab, per se, but I get better throughput when loading into the VMs if the source images aren't being scanned. For pete's sake, they're read only anyway.)
• *.vmdk
• *.nvram
• *.vmsd
• *.vmx
• *.vmxf
• *.vmem
• *.vmss

What I did NOT exclude were the files that I know are also file type extensions used elsewhere, such as:

• *.lck
• *.log