You might have thought that after a month of fighting crowds, spending money and panicking about picking out the right gifts, people might have taken a break from shopping the day after Christmas.

You would have thought wrong.

Merchants across the city reported brisk business Thursday from shoppers returning unwanted gifts and hunting bargains.

With a mediocre holiday shopping season behind them, a busy post-Christmas season is just what retailers are looking for.

Despite a better-than-expected sales surge after Thanksgiving, customers have been reluctant to spend, uninspired by a lack of must-haves and stymied by worries about the economy and jobs.

The compressed shopping season, which was six days shorter than a year ago, also had an impact on consumers, who never quite recovered from the lateness of Thanksgiving and seemed to delay their gift buying even more than usual.

Stores are counting more heavily this year on a spending frenzy during the last week of December, which traditionally accounts for about 10 percent of holiday sales, according to the International Council of Shopping Centers.

In Lawrence, many shoppers said they had hit the shopping trail Thursday just for the fun of it.

“Today we have to accomplish nothing,” said Connie Blodgett of Topeka, who was shopping downtown. “This is much easier — everybody seems more relaxed.”

Some shoppers were looking ahead to next year’s holiday. At SuperTarget, bargain hunters took dead aim at Christmas decorations that were discounted by 50 percent.

“We’re very busy today,” said Brett Schubert, the store’s manager. “They’re looking for bargains, and we’re seeing lots of gift cards redeemed.”

Downtown merchants were grateful for the business.

“We’ve been really, really busy,” said Anne Yetman, former owner of cooking-supply store The Bay Leaf, as she worked a shift at the Massachusetts Street store.

“People are buying things for themselves, they’re buying late Christmas presents. They’re just buying.”

Some stores were busy without making a lot of money, however.

“I’d say it’s mainly returns and exchanges,” said Scott Spal, a sales associate at Backwoods, a camping-supply store. “We’re not making the big sales we were before Christmas.”

Other shoppers were on the hunt for discount goods, Spal said.

“We’ve had a lot of people ask us about after-Christmas sales, when ours will start,” he said. “They’re definitely looking for the sales.”

Gail and Gerald Kipp had their hands full of shopping bags from downtown stores Thursday afternoon as they walked along Massachusetts Street.

“We shop to get great bargains,” Gail Kipp said.

“It’s a holiday tradition. We come down to Mass. Street, have lunch and shop. We’re so busy before the holidays. This is kind of a play day.”