The answer to your question is that, although TurboTax (part of Intuit, Inc.) is both the developer and publisher of TurboTax software, we act as well in a merchant capacity to sell our software directly to customers. We also work with many other retailers and authorized vendors. Those include such well-known companies as Walmart, Amazon.com, and Costco (just to name a few).
While we at Intuit may suggest or recommend retail prices to our independent vendors, it is actually against United States law for us to set or fix prices uniformly or arbitrarily. Therefore, each authorized re-seller of TurboTax can charge what they want to charge, for any given TurboTax product, based on their own supply of the software we have sold or licensed to them, as well as their own customer demand.
We do absolutely guarantee that the underlying TurboTax software code is the same for any given version of the program (Deluxe, Business, etc.), no matter from which licensed vendor you buy it, just as if you purchased the software from us directly.
That said, and speaking from the point
of view as a price-conscious consumer, as long as you feel comfortable
buying TurboTax software from a specific merchant, and you can be
assured that the product is genuine (not fake or copied), then probably
the smartest choice for you to make as an individual is to buy the particular TurboTax software version
that you want, at the lowest price you can pay for it.