That's how every car I currently own and every car I've recently owned works. To my recollection, I can't think of a car I've drive that didn't work the way described (friends, rentals, etc.). What car did you own that functions contrary to this principle?
A trunk or hatch is a place of secure storage. It shouldn't be available as far as I'm concerned if you don't have the key present. I don't always roll up windows at a gas station so I surely wouldn't want people to have access to the trunk or hatch just because the passenger compartment is accessible. In fact, my non-Kia cars have a key to lock access to the trunk or hatch thru the rear seats. You can lock it at your discretion so access to the interior doesn't provide access to the trunk.
You could always lower a rear seat back to reach the hatch in the Seltos.
A trunk or hatch is a place of secure storage. It shouldn't be available as far as I'm concerned if you don't have the key present. I don't always roll up windows at a gas station so I surely wouldn't want people to have access to the trunk or hatch just because the passenger compartment is accessible. In fact, my non-Kia cars have a key to lock access to the trunk or hatch thru the rear seats. You can lock it at your discretion so access to the interior doesn't provide access to the trunk.
You could always lower a rear seat back to reach the hatch in the Seltos.