Yes, it's only possible with the commercial edition:
you can remove the joomla account creation. That can be done by changing the option "registration" to "no registration" in the config of hikashop in the commercial editions. In that case, only the email address and the address of the user will be asked.
Indeed, there would be no shipping address. It's the expected behavior. When you sell digital goods, you might not want to ask the address of the user in order to increase the conversion rate as you don't need it for the sale. Also, some users will use the address collected by paypal or moneybookers and they don't want hikashop to collect it. In both cases, it's a valid use of that third option.