When addressing customers, it has become de rigueur to respect people who do not wish to receive advertising when selecting target groups.
Entries on the DDV Robinson list (as of 04/17): 909,000
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That the customer should be king is slightly dusty wisdom. Nowadays, it might be more the case that customers don’t want to be treated as sovereigns, but as enlightened counterparts. They know their rights, so correctness is required. It must be clear in all customer approaches that the legal standards are being adhered to.