As long as no-one has a dominant market position, such a deal is completely legal and there is nothing wrong with it. It used to be legal regardless of your ma

As long as no-one has a dominant market position, such a deal is completely legal and there is nothing wrong with it. It used to be legal regardless of your market share, but during the tail end of the Gilded age, we learned the hard way that once someone gets big enough that they can kill the business of their customers/suppliers by refusing to sell to/buy from them, they can stop playing by the rules of a free market where they compete with others to provide a better product or service at a cheaper price, and instead entrench themself as a permanent monopoly that gets monopoly rents and does not have to fairly compete. So, antitrust laws were born, which limit the kind of actions you can take if you have a commanding market position.