Hello,
Apparently, you have to force users to create an account or login otherwise shipping info is not available.
Your issue isn't directly related to user being logged in or not, but to the fact that your customers will need a shipping address which should be attached to his account/email.
The solution can be to set "Login" and "Shipping" actions through different steps on your checkout workflow that you can configure via "Hikashop->System->Configuration->Checkout".
Best regards,
Mohamed Thelji.