Public VPN services have to be the one of the greatest lemon markets to have ever existed:
You want people's private data? People will pay you to give it to them. Go ahead and sell the service for less than it costs due to the boatloads of data that you get.
People realize this, so you end up getting a disproportionate number of customers that don't worry about you getting their data because they're only using the service to behave abusively... which drives up costs.
So an honest provider has to deal with dishonest competition selling below cost and a customer base that is saturated with problem customers because good customers are savy enough to avoid VPNs.