Must I get permission to list businesses in my business directory?

Your business model is flawed,. Ask for permission, and charge a modest fee. Anything in this world you get for nothing isn't worth much. Your advertisers will want to know the intended circulation, and you can expect a few to say no, but you will be off to a financial success. As to the paid features, that is still an option! While you probably could just make a list without permission, you will never be criticized if you ask. Offering free service is asking to be abused. You will be criticized for offering a free service, and then not putting every name on the top of the front page. Good luck!