Many do sell software. Google is a major software provider. However, it is things like Google Apps for Work and Google Apps for Education, for example. The famed buzzword: software as a service. More and more people are paying monthly for software. There's also a lot of software being sold to companies for their work - B2B rather than business to consumer.

As was famously said a few years ago "Software is eating the world."

Even traditional software companies with on-premise licensing rarely send CDs nowadays.