Light cream is different than extreme pale or white. Owners of "white" goldens have bypassed this by registering their dogs as light golden. The problem is that dogs can be "registered" even if they have serious faults. Therefore, specimens with super pale coloring or off colors are being registered, but these super pale/white colorings are faults.
I looked up the AKC website and here is what it says about registering dogs who are not listed as standard colors, "While some colors may be disqualifications within the breed standard, dogs of a disqualifiable color may still be registered. However, AKC may ask for color pictures of the dogs before registration." I am guessing upon seeing some dogs; if they are truly "white" and don't look like purebred goldens, their application may be rejected.
Now, things are different if you have a light golden. Fact is genetical, goldens are various shades or golden ranging from dark to light. A white color should be impossible to produce in the breed due to their genetic makeup which should produce only gold, hence why the option of registering any other color other than dark gold, gold, and light gold is not offered.