"After gaining monopoly ..., the Omni-Tek corporation has steadily produced a better and more sparkly champagne."

Doesn't make sense, since once you have a monopoly, you don't have no competitors anymore, therefore everybody who wants to buy champagne has to buy yours anyway ... resulting in no need to improve the quality of your product. Funny that Omni-Tek is supposed to be a global or even universe-wide mega-company and does not understand that!?

You answered your own question when you said "everybody who wants to buy champagne has to buy yours anyway." The key word is 'WANTS.' If someone doesn't want to buy your product, it doesn't matter if you're the only one making it. If you can improve your product, you can increase your customer base by appealing to people who were not willing to purchase the lesser quality version.

You can also implement various price-points, selling a range of qualities with each higher-quality version coming at an increased price to appeal to groups of people with differing amounts of disposable income. Someone may only be comfortable forking over the money for the top-shelf Champagne on a vary rare occasion, but having a lesser quality one that they ARE comfortable with keeps them buying the rest of the time. Another customer may have plenty of cash to burn and be willing to buy the primo stuff just to fill their bathtub with.