What does that mean - Investigation of what? By whom? and on what basis/framework? Can you propose something workable?

In any case, there are many reasons a company can offer a better deal - they have invested money and developed a new product/service that the competition cannot simply copy or negotiated a better deal with a supplier, or they're simply a better managed company, or about a million other things businesses can do to gain leverage over competition.

Also, like a closely fought game - the advantage could just be temporary. These things are very fluid.