Usergroups Allowed To See The Buttons, this depends how is been made for every site. I have them all in one user group.
They only change they have is Ranks, 1 post, 3 post, 40 post and so on.
This does not effect to secondary user group, you and someone else maybe have it different than mine user groups,
I have checked this in other sites where I don't have any post. i have the privileges to request a friendship.
Anyway its just a Feature Request, if some else has same idea will see.
thanks