Many people have abandoned direct mail for what they perceive is more effective methods such as email marketing. While I will grant you that email marketing is much less expensive than is direct mail marketing, it may not be more effective. (And no this is not a promotion for the US Postal Service. In fact, you can read an earlier post we had about them.)
For a direct marketing piece, whether email or snail mail, to be effective it first must be opened. Free emails that are unopened are ineffective no matter their low cost. Recent data reported by Hubspot from their sources suggests that the average open rate for direct mail (snail mail) is 56%. Data I have seen for email campaign open rates is materially less than half that open rate. So while email may be more cost-effective to send, you may be missing the boat if you have abandoned snail mail as a campaign activity as well.