As i turn on invite anyone plugin, all new registered members (without invitation) get invitation emails to all groups on buddypress site (2 of them).
If I send an invite to a new user and check 1 group - he/she still gets invitation to both groups (2).
Invite Anyone doesn't seem to care or understand which groups I select and when it needs to send e-mail invitations.
Right now it sends e-mail invitation everytime & to all groups. So I don't have any control over this matter.
As a result I have this plugin turned off - to prevent new members who register without invitation being invited to all groups.