Recently I've been reminded that actually people make software that you can't just dip into, that you have to buy. This is partly because I now work for Ibuildings and we're Zend Partners - so all of a sudden I have access to lots of Zend products that I haven't had reason to play with before. I also have a new work laptop that came with Windows Vista, which was less horrifying to use that I'd feared, and nothing like as good as I'd hoped. I'm sure half of the problem is that I really haven't used windows for a long time, and its quite hard to find your way around unless you're used to doing things that way.
The very idea of paying for software feels new ... it isn't, of course, but its been so long since I had anything that didn't come out of my linux package manager, or from sourceforge that it really caught me by surprise. A lot paid-for software is easy to make points against - its proprietary, closed softare, or the same thing could be achieved by free equivalents. Which is true but if you're not actually going modify the code or use the contributions of a wider community, it probably doesn't matter. And if you aren't going to install, set up, and glue together one or more free products, then the paid-for version is probably more up your street. On the whole, there are definitely situations where I can see the point of paying for a better-packaged version, or one that combines one or more functions, or offers support.
Then there's the aspect that commercial software comes with salesmen and things - there's a lot to be said on both sides! I'm not sure I'll be putting my hand in my own pocket for software any time soon, but working with new products is interesting and I find I really would recommend some of them to others. I'd love to hear others' feelings on this topic as well!