Or they paid for it because the alternatives weren't any better. Visual Studio Debugger is very nice, I don't know of anything that's as good, and as mature. Attach To Process with a nice UI is a great tool compared to the command line debugger.
VS 2008 and 2010 are worlds better than 2005 -- so if we count the last 10 years nearly half of that will be people using 2005, and yes that was awful. Two version later, is it worth asking for a good price for a full featured version? Probably.
DDD, Netbeans debugger and Eclipse's debugger are on equal standing. I've used all heavily.
However, I tend to rarely use the debugger on my own code in any language since I started doing incremental TDD and using assertions galore all over the place to check inputs, outputs and assumptions. Prevention is better than cure (or debugging).
You can't assert everything, you can't test everything (like the tests themselves).
You can't assert a list of hard coded values are all correctly spelled via an assert. You can't determine if a library that has it's own asserts is failing or your code is failing. You can't always add asserts to legacy code, etc.
Hats off to you if you can use DDD heavily. I've given up on that shortly after every time I've tried to use it. It seems very prone to crashes and lockups. MSVC will too sometimes, but it's really pretty rare.
VS 2008 and 2010 are worlds better than 2005 -- so if we count the last 10 years nearly half of that will be people using 2005, and yes that was awful. Two version later, is it worth asking for a good price for a full featured version? Probably.