Only a few short years ago, the holiday shopping season actually started on the Friday after Thanksgiving. Starting early in the morning on Black Friday, consumers would line up in front of their favorite stores hoping to get their hands on heavily discounted items that were available in limited quantities.

However, that has changed. Now many chains open their doors on Thanksgiving Day, pushing the start of Black Friday into Thursday. It's a practice many people don't like, partly because it forces employees to leave their families on the holiday, and partly because some consumers feel that to get the best deals, they must go shopping on Thanksgiving.

Putting the ethics and emotions aside, when you look at new data from Foursquare, the answer is pretty clear. The research, based on the self-described "location intelligence" company's ability to analyze foot traffic at various retailers, shows that if stores opt to stay closed, they likely won't make up the sales they miss out on.

Woman carrying shopping bags looks at her phone.

Not opening on Thanksgiving likely means losing sales. Image source: Getty Images.

What does the data say?

For the first part of its report, Foursquare examined retailers in New England along with Pennsylvania and New Jersey. Three of those states, Massachusetts, Rhode Island, and Maine, have laws dating back to colonial times that prevent retailers from opening on Thanksgiving.

The three states that were closed on Thanksgiving saw foot traffic increase by 23% over Thanksgiving weekend (Thursday through Sunday) in 2016 compared to a baseline weekend, according to Foursquare data. In the other states, Vermont, Pennsylvania, Connecticut, and New Jersey, where retailers could legally open on the holiday, foot traffic was up by 35%.

"This showed us that retail performance over the full weekend was significantly higher in states that allow shopping on Thanksgiving Day," wrote Foursquare's Jeff Glueck.

The data showed that foot traffic across all the states in the study (New York was left out because of its size and the number of tourists it attracts) saw comparable increases on Black Friday and through the full weekend. In addition, the research uncovered another strong sign that retailers should open on Thanksgiving.

"In New Hampshire, 29% of retail traffic on Thanksgiving Day is made up by visitors from Massachusetts, Rhode Island, and Maine (a significantly higher proportion than an average Thursday)," wrote Glueck. To make matters worse for stores that don't (or can't) open on Black Friday, 60% of those shoppers did not do any shopping in stores in their home states on Black Friday.

There is a bit of a caveat with that stat. New Hampshire does not charge sales tax, which is certainly partly responsible for some of the cross-state shopping. Still, Foursquare called being closed on Thanksgiving "a major missed opportunity."

The early bird gets the worm

Even though most shoppers will exceed their holiday budget, most work with a finite pool of resources. If a chain does not open on Thanksgiving -- even if that's the right thing to do for its employees and their families -- it misses a chance to compete for customers that it won't get back.

Even if all brick-and-mortar retailers opted to stay closed, those without robust digital operations would still lose out. Opening on Thanksgiving may not be what many companies want to do, but it's clearly what they have to do in order to compete.

Consumers could change that by staying home and refusing to shop online or in stores on a day that used to be all about spending time with family, eating, and watching football. Since that's unlikely to happen retailers have no choice if they want to maximize sales.

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