Suppose I work at Microsoft. I would probably write the bulk of my code using Visual Studio, which is one of Microsoft's most popular projects. Therefore, dogfooding.
Now suppose I work at Netflix, which provides a video streaming service for entertainment value. I'm not going to watch House of Cards on the job (wink). I might when I get home, though. Can an employee's use of a company's product off the clock (e.g. entertainment software, tools for personal projects, etc.) be considered dogfooding?