U.S. v Socony-Vacuum Oil Co., 310 U.S 150 (1940); United States v. Sealy, Inc., 388 U.S. 350 (1967); United States v. Topco Associates, Inc., 405 U.S. 596 (1972); Craftsmen Limousine, Inc. v. Ford Motor Co., 363 F.3d 761 (8th Cir. 2004), Northern Pac. Ry. Co. v. US 356 US (1940); Agnew v. National Collegiate Athletic Ass’n, 683 F.3d 328 (7th Circ. 2012); or In re Flat Glass Antitrust Litigation 385 F.3d 350 (3rd Cir. 2004), National Soc. of Professional Engineers v. U.S. 435 U.S. (1878); In re Insurance Brokerage Antitrust Litigation, 618 F 3d 300 (2010); or In re Southeastern Milk Antitrust Litigation, 739 F.3d 262 (2014).
I picked one at random.
“Topco, a cooperative association of about 25 small and medium-sized independent regional supermarket chains operating in 33 States.”
I also looked up one about Ford vs a limo company that you deleted.
They all involve multiple companies colluding. It has nothing to do with one company setting prices in their own store.
You seem to be under the impression that anti-trust is isolated to monopolies, when clearly it is not. Apple and Google do not need to have a monopoly for the government to decide that their app store business model is anti-competitive, and there doesn't need to be precedence.