BRUSSELS—Some U.S. tech giants may prefer to pay a fine rather than comply with antitrust rules, the European Union’s antitrust chief said, and cited Apple’s fight with the Netherlands’ competition authority as an example. The Dutch Authority for Consumers and Markets (ACM) imposed a 5-million-euro ($5.7 million) fine on Apple on Monday, the fifth such penalty in successive weeks, linked to claims that Apple does not allow access to non-Apple payment methods for subscriptions to dating apps. European Commission Vice President and digital chief Margrethe Vestager said Apple’s behavior could indicate other big companies behave similarly. “Some gatekeepers may be tempted to play for time or try to circumvent the rules,” she said in an online speech at a U.S. awards ceremony on Tuesday. “Apple’s conduct in the Netherlands these days may be an example. As we understand it, Apple essentially prefers paying periodic fines, rather than comply with a …