In more simple terms, Zoosk doesn't make their users fill out their profiles unless they want to.
Their "Behavioral Matchmaking" system takes a users' patterns throughout the site to determine who they'd be most suited to romantically and/or sexually.
Payment is accepted by credit card, check money transfer or Pay Pal.
To cancel a subscription, you must log into Zoosk, go to the "Settings" tab, and then "Subscription".
Most of the profiles I encountered mentioned some sort of casual dating interaction.