I think it is monopolistic. If one company has so much influence in your life that they can direct you to their own products, so that you habitually start relying on them for almost anything, then they have the ability to develop a wide range of monopolies by influencing your choices. E.g. Google has a monopoly as a trusted source of all information - what's even stranger, is that they are seen as a non-interfering third party by most users - because of this, many other monopolies can emerge, because they have the ability to control "truth" and "popular opinion".
By that logic, Walmart would already be a monopoly in the perception of quite a few people in America, which is clearly not the case to much of the rest of the country.
