Daptiv really isn't designed to be an email distribution or management tool in this way, so there isn't any kind of email address aggregation like you describe here. However if these individuals are either active Daptiv users or External Resources, you can use the Notifications feature to distribute information in bulk without having to explicitly select each person, especially if you use the Workgroups function to create "distribution lists" of users.
Alternately, you might want to look at creating a formal distribution list in your corporate email server, then send the desired communications to that list for distribution.