Sandboxing and Requester Groups

It seems the Sandbox environment doesn’t make an exact copy of the prod environment when created. I find that many of my Requester Groups are nowhere to be found in the Sandbox, which is unfortunate when I need to test Service Catalog item visibility. The documentation on sandboxing explicitly says groups are copied, and the verbiage on the Sandbox page in the admin portal seems to suggest it is creating an exact replica of the prod environment when the Sandbox is created. I have been told, however, by support that this is not the case, and the Sandbox doesn’t load all the Requester groups (and possibly other items but I haven’t checked everything yet). This needs to be fixed, else the Sandbox is useless (for us anyway) for staging changes to be loaded into Prod, something the literature and product videos suggest is its primary use-case scenario.