Thanks to deeply buried clauses that allow "affiliate sites" to share information, your personal profile may be sold to start-ups:

[E]very new dating site faces the same problem: finding souls to mate. Recruiting new customers is expensive; industry experts put the customer acquisition price at $1 to $5 per person. SaleDatingProfiles and its competitors BuyProfiles.com and DatingProfilesSale.com offer a shortcut.

They sell bulk packages of profiles that seem to include a fair number of actual singles alongside somewhat more questionable Russian beauties, Nigerian bankers and half-empty profiles, which sometimes sell for less than a dime a dozen. Betabeat emailed 208 men and women whose profiles are being sold on SaleDatingProfiles. Most didn’t reply; 35 emails bounced. Only five people responded, none of whom knew their profiles were for sale.