Joel,
Have you contacted the manufacturer directly yourself? At the very least you may get clarity on the issues between the manufacturer, supplier and retailer. If the manufacturer really does refuse to give you a free upgrade to XI, there may well be very good reasons for that... but those same reasons may well give you the right to return the goods. Worth a shot!
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1