Anti-trust laws basically says that if you have a practical monopoly on one area, you are not allowed to tie your products in that area with products in other a

Anti-trust laws basically says that if you have a practical monopoly on one area, you are not allowed to tie your products in that area with products in other areas. Its not that simple. Monopolies are not inherently illegal, they only become illegal when they are maintained artificially. Also, the Sherman Antitrust act is usually applied more subjectively than most statutes, with the final decision turning on whether or not the alleged violation is "harmful" (to the consumer or the market as a whole). In other words: if your product is simply better and you have a de facto monopoly as a result, that's legal. If you protect your monopoly by making competition itself impossible, that's illegal (but hard to prove).