There is a cost associated to creating an account on Steem blockchain. When you create your account on Steem blochchain using the Steemit interface the charges are paid by the Steem Inc. Since they are paying on your behalf for creating the accounts they generally take some time to verify the accounts making sure that it is not spam.

You can suggest the following approach to them https://steemit.com/utopian-io/@roxane/how-to-create-a-new-steem-account-with-steemconnect if they need to create their account real quick and are ready to pay the price.