Amazon may buy upstart Jet.com: Munster

Amazon's 'Prime Day' bonus

E-commerce site Jet.com hasn't launched yet, but it could be an acquisition for Amazon.com, Piper Jaffray Internet analyst Gene Munster said Friday.

Jet.com is set to open for business next week and will offer discounts on millions of items to customers who pay a $49.99 per year subscription fee. The twist: As users add more items to their cart, they have the opportunity to mine deeper discounts, creating an incentive to keep buying, Munster said.

The start-up was co-founded by Diapers.com co-founder Marc Lore, who sold the baby products business to Amazon in 2010.

"I think Jet has something. I would definitely check it out. When you buy things, it kind of gamifies the buying process, and separately, they do really well with the fast-moving stuff for your home," Munster told CNBC's "Squawk Box." "That's something that historically, Amazon hasn't done as well in, so they're trying to really tap into that Costco type of consumer."

Read More Why Google will score more earnings beats: Analyst

Munster said Lore is a "rock star" when it comes to online retailing and Jet has a good chance of succeeding. If Jet does become a hit, Amazon is more likely to buy it than to copy it, he said.

Responding to criticism of Amazon's first annual Prime Day, which some likened to an online garage sale with steeply discounted but random items, Munster said, "It might have been a garage sale, but people showed up."

Amazon Prime is the company's subscription member club. Thursday's Prime Day discount event was only open to those members.

Piper Jaffray estimates Amazon will add 2 percent to unit growth for the current quarter from Prime Day alone. "Two percent is a material day. That actually is something that as an investor you should factor in to how you think about the September quarter," Munster said.

Read More Amazon selling items for less than on Prime Day

The firm has a price target of $520 on shares of Amazon. The stock closed at $475.48 on Thursday.

"We think the unit growth is going to be a surprise for people on the upside," Munster said. "As investors start to think about this as a unit growth story once again, that's going to add even further upside to
Amazon's multiple."

The unit growth is being driven mostly by Amazon Prime users, who spend about seven times more than regular, he said.