You're missing the fact that a flatscreen TV will still often represent - as a portion of someone's wealth - a far greater cost than a private jet would to a billionaire. Consider that most low income people are getting their cell phones on payment plans, whereas a multimillionaire can afford to buy a Lamborghini Gellardo out of pocket. On top of that, high end purchases like cars, yachts, houses, fine art, etc, often retain a lot of their resale value, turning them into investments in many cases, often reselling for more than their purchase price. So yes, I absolutely did account for the tax exemptions on "essentials", and even when you factor those your sales tax only model still ends up being less onerous the more wealthy someone is.

I also want to call out the unspoken implication that is often present with these theories - not accusing you of doing this, but it needs to be said - that items like phones, computers and TVs are extraneous luxuries that no poor person should ever own, as if enjoying a fulfilling life or engaging in relaxation are things that only the wealthy should be allowed to have access to.