Members use the bikes heavily, which requires maintenance, and people who drive around Manhattan taking bikes from popular parking spots and bringing them to popular departure spots, and recharging electric bikes. This is very imbalanced, EG everyone wants to go to Grand Central in the morning and leave from there in the evening.
In addition to the marginal cost from each member, Citi bike has high fixed costs, like maintaining the bike docks. My guess is that even at $205 for a membership Lyfy doesn't profit much.