Extra field with a default value?
 

Is there a way I can add extra fields that have a DEFAULT value to each new customer's profile or to each order? I have added blank extra fields successfully (for example, for Gift Tag during checkout). But I want one that has a default value assigned.

Alternately, is there a way I can use an existing, but unused. field and assign it with a default value. For example, I don't use the tax ID and SSN fields for anything.

I'd like to add this to multiple stores currently with versions 4.1.9, 4.1.10, and 4.3.1, and a new 4.4.2 store I will be doing soon.