But while regulators might be dubious, Amazon's wide-reaching business is still nowhere near a monopoly, according to Ethan Kurzweil, a partner at Bessemer Venture Partners.
"I don't think they're a monopoly really in any category," Kurzweil told CNBC's "Squawk Alley" on Friday. "You'd have to establish that they have market dominance somewhere. That they're the only alternative for some particular thing. And I just don't think that they're really anywhere near that threshold yet."
Kurzweil said he worked on the Microsoft anti-trust case as a young intern in Washington. In that 1990s case, Microsoft was accused of constricting competition in the software industry by using its arrangements with other companies, and its control of Windows, to promote Internet Explorer over Netscape. Kurzweil said Microsoft had control of one distinct market and leveraged it for the benefit of another, which is not quite the case in Amazon's markets of commerce, media, logistics and cloud.
"They don't have a monopoly in online commerce yet, it's less than 50 percent market share there. They're not necessarily doing anything wrong, from a monopoly standpoint, under the laws we have. You'd need more aggressive anti-trust enforcement to pull them back," Kurzweil said.
Senator Cory Booker (NJ-D) for one, has said otherwise. Booker told Recode that the government needs to be more critical of deals like Amazon's planned acquisition of Whole Foods. President Donald Trump has been critical of Amazon and CEO Jeff Bezos, but has also pledged to roll back regulations that restrict business deals. Amazon has called analysis of its pricing practices "deeply flawed."
"Europe's leading the way. They did a very thorough — I thought reasonable — investigation on some of Google's practices," Kurzweil said. "Senator Booker's right. The U.S. has not led in that area lately. I don't think it was any different under Obama, frankly. ...We haven't seen any signals from this administration that they're planning to be particularly harsh."
Still, Kurzweil said, the FTC probe into Amazon operates under a different set of laws from anti-trust regulation, which might prove more challenging for the company.
"It's got to be on Amazon's radar," Gene Munster, managing partner at Loup Ventures, told "Squawk Alley." "Lawmakers are going to progressively put more scrutiny on these companies."
In content, for instance, Amazon could prove to be a real competitive threat for Netflix, Munster said. But other companies, like Apple, are also improving their video content offerings.
Then in cloud, another Amazon-driven industry, Microsoft is turning a corner.
"There's still quite a bit of IT work to make that transition seamless, and make that migration," Kurzweil said. "I don't think we've seen the, 'IT work is dead, it's now managed by four companies,' vision that perhaps was the fear was a couple of years ago."
Technology companies, and ultimately consumers, will still be winners over government regulation as Amazon and other companies offer lower prices and more convenience, Munster said.
"As they get bigger, and as these companies affect more and more people, they're going to get more and more scrutiny," Kurzweil said. "I think generally speaking, most people would agree that Amazon's been a good thing, and they're able to have more choices ... I think that scrutiny, they're going to get it, but I'm not sure it's going to have an impact. At least, in the near term. Until they really overstep that line, as Microsoft did in the 1990s."
— Reuters contributed to this report.