They're not envelope stuffers. A profile of people who work from home shows they are more likely to be knowledge workers.
Here's what GlobalWorkplaceAnalytics.com reports.
"On average, a telecommuter is college-educated, 49 years old, and earns an annual salary of $58,000 while working for a company with more than 100 employees. 75% of employees who work from home earn over $65,000 per year, putting them in the upper 80th percentile of all employees, home or office-based."
Another source, FlexJobs.com gives the same profile, but interestingly says they/we typically work with a company with FEWER than 100 employees, not more. Am thinking one of them made a typo.