That’s my thought, these are worldwide numbers, so while the “premium” VPN services are popular in developed countries where most have the disposable income to afford them, those in developing countries may find the free services much more accessible, even if they aren’t as reliable. Income may not even be too much of a factor, sometimes software or services can get popular in places like India where there’s just a very high population. India played a big part in worldwide desktop Linux growing to 4% market share, for example.