Amazon, Google and Facebook warrant antitrust scrutiny for many reasons - not just because they're large

There’s a growing chorus of U.S. politicians, antitrust scholars and consumer watchdogs calling for stricter antitrust treatment of Amazon, Google, Facebook and other tech giants. Some even say they should be broken up. Most recently, U.S. lawmakers launched a sweeping review to determine if these companies have become so big and powerful that they are stifling competition and harming consumers, while federal regulators are also gearing up to take action. But, when it comes to whether Silicon Valley giants are abusing their market power, size is only part of the problem