Exactly. I have a Bosch drill and I recently had a carpenter trying to convince me that I should have spent three times as much on a Makita. He was basically trying to show me that the cheaper drill was a false economy. Its hilarious in software how much time we waste dealing with poor tools. Some free tools are excellent but in many cases spending some money will save you so much time and effort, enabling you to make more money and giving some of that to the developers. Wins all round.

Why is it strange? Lots developers who write free software get paid for their work.

Only in areas where software is not the main product.

How did you come up with that?

Mozilla is a clear example of people paid to write FLOSS. I used to work at a foundation that did that too. There's plenty going around.

Mozilla is a clear example of a software that isn't the product being sold.

The product being sold is the service to access online web sites, sell search data to engines and online advertising.