Why Separate Email Account for Directory Submission
A directory submission is a process of submitting URL to various web directories either to do it manually or by automatic software. All directories submission form has email column which is compulsory in all cases. So you need email ID and domain email works better as directory editor have confident that submission is genuine. Now the question it that why it should be separate valid email the reason are:

Free Directory Submission Gets You Tons Of Quality - 1 Way Links
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