There are plenty actually. I don't know why, but some companies chose VB.net over C#, probably because they used to be VB shops, possibly because they feel VB.net is a better language (!)
I know of a very large design suite that is used for oil platform and ship building that has a large part written in vb.net.
I know nearly all the health system software for the UK NHS is written in VB.NET now.
The difference between C# and VB is tiny, VB has a few really cool features in there that makes it a better language that C# all in all, it's just that most people don't like its syntax.