Why item is not mandatory field during enter requisition line

Summary:

When we create catalog requisition through Enter Requisition Line, item field is not mandatory. So a user can use this as non-catalog request, since item field is not mandatory and he can enter description and move ahead. I want to understand why item field is not mad mandatory for catalog requisition line?

Content (please ensure you mask any confidential information):

Version (include the version you are using, if applicable):

24B

Code Snippet (add any code snippets that support your topic, if applicable):