those membership levels are not purchasable by members and will only be seen if that user has that membership type. They are setup to not be modified as they are essential to the way Dolphin runs.
The promotional membership will not be activated unless you do so.
A non-member is basically the same as a viewer who is not logged in.
And the standard is the default membership when someone hasnt paid their membership fees. As well as the default membership a user gets before being allowed to upgrade.
As it stands right now, I do not believe there is a default way for us to setup a Dolphin site that will require payment of/selection of a membership level other than standard upon signup. There may be modules, but I do not know.
in order to create custom memberships that a user can purchase, you must install the Memberships and Payments modules. Unfortunately, even if you setup a membership that was free, it still goes through the whole checkout and payment process.