Ma Table Halal is free and always will be: no paid features, no advertising, no visibility for sale.
The registry is funded by the time of its author, an independent infrastructure and data engineer. What he gains from it: a public demonstration of his work, a real service that is dependable, fast and respectful of data. The registry is his business card, not his line of business.
The contact details entrusted by owners are used solely to manage their listing: they are neither sold nor used for canvassing. Their only possible disclosure is the one required by law (judicial request), detailed in the privacy policy.