In addition, Price says a program like Amex's, with its 15-minute time limit, allots little room for the customer to abort the purchase. Amex's Berland says the company uses the window because it reserves inventory for shoppers after they tweet the hashtag; the company can only hold the product for so long.
That pressure-cooker effect isn't typically part of an in-store shopping experience, says Price. By physically being in a brick-and-mortar shop, consumers may catch employees and other customers shooting them dirty looks if they arrive at the checkout line and then decide to put products back on the shelves.
With a virtual shopping cart, there are no onlookers casting judgement. Nearly 90 percent of online shoppers have abandoned an online cart, according to a 2010 report by Forrester, a research and advisory firm. In fact, several studies show online consumers abandon their carts about 25 percent of the time. However, Twitter publicly displays a customer's tweet-to-buy purchases, so the embarrassment of canceling a purchase is still a factor.
Others worry about the security of consumers' credit cards. "I'm scratching my head on this one," says Deena Coffman, chief information security officer at IDentity Theft 911, a Scottsdale, Ariz., company that provides identity and credit protection services for families. She questions the safety of the platform, adding that Twitter is notorious for being hacked.
Twitter accounts are, indeed, vulnerable, as exhibited by recent hacks on major companies. For example, attackers broke into Burger King's account in February and tweeted the company had been purchased by McDonald's. Other compromised accounts created a more alarming stir: On July 4, 2011, Fox News's account tweeted President Obama had been assassinated; NBC News's Twitter reported on Sept. 9, 2011, a plane had crashed into "Ground Zero."
While many companies (including Amex) offer protection to customers in the event their credit card information is confiscated, Coffman fears consumers are too exposed when making tweet-to-buy purchases.
Despite such concerns, consumer behavior consultant Graves thinks many people will take advantage of the program. He adds social networks also stand to benefit: "Just as any entrepreneur seeing a crowd of people walking past on the way to a ball game will wonder if there is a way of putting a hot dog or merchandising stall by the side of the road, I think it's inevitable that large social networking forums will seek to capitalize on their ability to attract large numbers of people."
The bottom line: For credit card users, these programs come with risks, but a tweet-to-buy business model satisfies the typical consumer's desire for convenience, deals and responsive customer service—and, with a simple hashtag, gives them a chance to show off their shopping smarts.