When you currently invite users to other profiles they are almost a 'guest user' so their admin rights on their original system are not replicated on the profile they are invited to
It would be useful when inviting users to other profiles to have the option to either set them up as a guest user as it does currently, or be able to give them admin rights (either the same level of admin permissions they have on their original profile, or different permissions)
Jess Cowell has spoken to DJB and AHA about this and it is actually a bug because it should copy across their admin permissions that they had set on the original profile
However, I think it could still be useful to have the option when inviting users as in some scenarios you may just want them as a guest user without any admin rights, maybe with the same admin rights or even not all the same admin permissions