That would seem to make sense to me. Putting it another way, that's what I'd do if it was my business. Just like some properties have unofficial levels for their best repeat customers - I know that the properties where I do the most Hilton family and Starwood stays respectively treat me far better than the run of the mill top-tier.

They have a field in a database that can contain a digit. Why wouldn't they use all ten possible values to mean something??