Devices on the network use unique identification such as mac-address. As a use case, do you want to assign a specific IP address every time to VIP's laptop? Or Do you want to categorize based on type of device..such as Apple TV or iphone or some other manufacturer...
Basically, network cannot identify the role of the use in the organization just by looking at the device. Yes, with the help of dhcp fingerprinting, we can identify the type of device..