First of all, lets consider that we are talking not about *controversy*, but *legal challenges*. It's a fine but important distinction.
Then, think about human technological progress throughout the centuries, or maybe even think about the last few decades and name any other new service that opened up to legal challenges (not just controversy in its execution, but actually treading on legal gray areas). Sure, there's been a few, such as, say, assisted suicide, abortion, private investigation, cyber-security consultancy; but there have been *plenty* of innovative services that raise no such questions: telephone service, personal computing, shoe shining, electronic commerce, to name a few. All of these have been quite popular.
Google has not encountered legal challenges because it is innovating, but because they *choose* to. Their business model depends on the aggregation and sale of consumer behavioural information, and that particular endeavor is riddled with challenges, both legal and moral.