Hello,
All super-admin are attached to the main vendor by default.
Because a super-admin have access to all backend features ; by definition he has the same rights in the front-end.
Afterwards, you can create vendors in the backend and set an super-admin account as the vendor owner.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.