WESTERLY — While the styles and fashion trends of the ’70s are cultural low points many of us would just as soon forget (just take a look at your high school yearbook photo to remember why), they were cause for celebration — not to mention some pretty significant savings — at the Jonnycake Center of Westerly thrift store on Saturday.“Another 40 percent off the entire purchase!” called out one of the paisley-plastered cashiers ringing up customers at the shop and handing out peace-symbol necklaces, all in honor of National Thrift Shop Day. The entirely contrived — albeit fun-loving — holiday celebrates thrift-store shopping at a time when “thrift shops have been generally replaced with discount department stores” across the country, according to “Days of the Year,” the website behind the initiative.True to form, the staff and management of the Jonnycake Center rose to the occasion with their usual flair and fun-loving spirit.“We think thrift-store shopping should be like an attraction, where something is always happening,” said store manager Jennifer Eccleston, who wore a painted peace symbol on her face, like a go-go dancer from “Rowan and Martin’s Laugh-In.” Outrageous costumes and kitschy décor are nothing new to the center. It changes its theme every month to reflect either the season or simply one of Eccleston’s whims.“In July we had a Fourth of July theme. Other months it’s just whatever I come up with. The staff loves it. It’s like having a party every month,” said Eccleston.The good fun is for a good cause. The nonprofit center runs a food pantry and social service operation for needy families and individuals living in Westerly, Hopkinton, Richmond and Charlestown. Originally located in Bradford, the center moved to the cavernous old Guild factory at 23 Industrial Drive (behind the Amtrak station) in 2007. The enormous space has since enabled the center to carry a large inventory of used goods, from books, to toys, to furniture and kitchen items, to clothing.“For us, it’s about volume,” says Johnny Cake Center Executive Director Elizabeth Pasqualini. “We keep our prices very low so that we can keep moving inventory out.”This tried-and-true bargain-basement formula may make sense for many retail operations. But in the case of the Jonnycake Center, the motivation is more than just monetary.“The thrift store pays for the other things we do for the community,” Pasqualini observed. “Every time someone buys something there, they are helping someone else pay for medicine, or pay a heating bill, or put food on the table. And we’re doing it 25 cents at a time.” Big bargains were a key feature of Saturday’s event. Customers could select numbers, written in the centers of paper flowers, from a bulletin board that corresponded to various savings bonuses (e.g. half price on everything). Eccleston said game shows, popular during the ’70s, inspired the idea. Then there were just good, old-fashioned Yankee bargains.“I picked up this clam rake for $2,” said Heather McDonald of Bradford, who drops by every week to see what’s new in stock.Other customers, like 12 year-old Caleb Hodges of Hope Valley, were too young to remember the ’70s, yet nonetheless felt a connection.“I must have lived during them in a past life” said the hippieish Hodges, whose auburn hair hung to his shoulders. “Why do you think my hair is so long?”His big score that day? A wooden box that wouldn’t open, and didn’t seem to serve much of a purpose, but which he felt he needed to have anyway. In short, a metaphor for what the Jonnycake Center is all about: hidden treasures, veiled in a bit of mystery, that you just can’t resist.