Currently, in order to utilize the Requests and Purchase Requisitions functionality, an employee must request an item which has an Inventory ID. But, in the real world, employees often need to request non-inventory resources to perform their daily tasks. Examples:
Requiring an Inventory item for something that will never be stocked in inventory is inaccurate and should be unnecessary. We must either create a generic "Non-Inventory Item" as an Inventory Item, or allow the creation of many one-off items which will dirty the system for no real reason.