Earlier quoted context omitted.
Contractor are paid more, since they have to factor in the health insurance, taxes, unpaid vacation, perks, their own laptops, no need for office space, no 401k match. There is no reason they would ever get paid less. Maybe those with H1B visas who can get taken advantage of or outsourced contractors in Ukraine? Those contractors definitely get paid a fraction of US salary.
Contractors are almost always paid less in my experience after taking into effect stock grants and bonuses. The contracting agency probably gets a nice portion of the takehome though (for having the political capital of being on a preferred vendors list), so to the company they probably pay more than salary.
Factor in overtime, or the lack thereof, and you can make more or have far more work/life balance than FTs. That weekend app release? There's an extra $500-$1k that the FTs aren't getting. Company doesn't allow contractors to work over 40 hours for budgeting purposes? Leave at 5 everyday without anyone complaining.