Its often because buying the IP adds cost to the standard licence. So instead of having to buy the IP for every licence, you just get 1 copy, meaning only 1 engineer can compile a design with the IP in it at one time, while the other engieers can get on with other projects not containing the IP. Obviously, if every design requires the IP, you may need to buy more licences.
The netlist wont be limited to a node, it just means only 1 node can compile at a time.