"Hell No. Not My Dough" and "Macy's Is Just Wal-Mart with Pretension," read some of the signs carried by demonstrators, who also toted Field's signature green shopping bags.
The store is one of about 400 properties nationwide being converted to the Macy's nameplate by Cincinnati-based Federated Department Stores Inc., which acquired them when it bought May Department Stores Co. last year.
But unlike most of them, the big Marshall Field's store had amassed generations worth of loyalty.
Amelia James said she treasures childhood memories of dressing up in white gloves to have lunch in the store's Walnut Room with her grandmother, Grace Denny Elder. She said she was going to cut up her Field's credit card and boycott Macy's.
"My grandmother was born in 1898. She shopped here her whole life," said James, 48, of Chicago. "There were six kids in our family. We didn't have a lot of money, but when she brought us here to Marshall Field's, it was one of the most special things."
The store was built in stages from 1892 to 1914, and was open during at least part of that period. Its name came from retailer Marshall Field, who got his start as a salesman in a Chicago dry goods store in 1852.
James was one of roughly 100 demonstrators who objected to the name change Saturday morning.
At the same time, however, hundreds of shoppers had started lining up two hours before the doors opened. Once inside, they listened to a jazz quintet as they used $10 Macy's gift cards handed out to the first arrivals. Workers in Macy's T-shirts offered silver trays of complimentary doughnut holes and coffee in glass cups.
"Things change," said Chicagoan Mary Peterson, 64, the first person in line before the store opened. Peterson worked for 18 years at Field's, packing the store's popular Frango mints into boxes as they came off the conveyor belt in the candy kitchen. She said she welcomes Macy's and was planning to shop for shoes Saturday.
"My mother worked here years ago when she was pregnant with me. I feel like it's a part of me," Peterson said of Field's. She acknowledged feeling nostalgic, but said she didn't object to the name change.
Macy's will continue selling Frango mints, but without the name Marshall Field's on the box.
The Marshall Field's building, covering a full city block, was designated a National Historic Landmark in 1978. The department store occupies eight of its 12 floors.
Federated became the nation's largest department store retailer when it bought May. The switch to the Macy's nameplate will give Federated a total of more than 800 Macy's stores in 45 states, the District of Columbia, Guam and Puerto Rico.
The company spent months preparing for the name change, switching credit cards, store signs and advertising. Federated officials said they can give consumers better products and a better shopping experience by unifying the stores under the Macy's label.
Along with the Marshall Field's nameplate, a number of Saturday's protesters also mourned the loss of other consumer landmarks in Chicago. Carson Pirie Scott's State Street store is scheduled to close next March and the Berghoff Restaurant closed in February, although it reopened as the Berghoff Cafe in April.
"It's these icons of our city that make it special," said Chicagoan Michael Moran, 47, who wore a White Sox ball cap and carried a large Chicago flag.
He said Federated could have retained the Field's name by simply adding the words "a Macy's store."