Optional nodes in cvrp

[LaraOwob]

Hi, I have a question. I have a cvrp with multiple different cargo types, one depot, and mulitple pickups and deliveries. To create the depot inventory I created for each cargo n different nodes all containing one amount of the cargo type and made all the locations the same as the depot. The solver obviously does not have to use all the inventory every time so i tried making the dummy nodes (fake depot with 1 cargo) optional. The problem is I tried this with adddisjunction but adding a negative penalty is not possible, as i wanted to encourage the solver to drop nodes it does not need without using a penalty. Then i tried a zero penalty but it still tries to use almost all of the nodes. The only close to the result i get right now is by making all nodes optional and adding a very high penalty to the actual deliveries and pickups however it still drops some of them every now and then. Does someone know why