In an Allowed Values list on a property, what is the use of value vs label?

Summary:

I am trying to understand the use of Value vs Label in an allowed values list on a property.

Example of my value list for a property on my Common.Fund.nt

I see what when I set this up, the property shows the label, which is what I would expect. It appears that the value is what is used when validating the data type parameters, as my maximum length is 2, and I don't get data errors when selecting the labels in the property.

However, I notice that when the value is passed through a subscription and the converter is set to copy, it appears to pass the label, because the subscribing viewpoint/node type then throws an error on the property for the maximum length exceeding 2 characters.