When using a business email list, the most common and controversial topic will always be that of customer privacy. The many sides of the debate can range from two to four, even five. Some say it is mostly a consumer issue. Others say businesses are just as protective of their own information. On occasions, the debate touches on the political and philosophical sides of business.
That sounds distressing given that business itself leaves you enough to worry about it. Regardless, no matter how much anyone needs customer information (and to be fair, such a need can be justified), you have to expect protests and opposition on the grounds of privacy.