Shoppers at a Louisiana Fireworks pop-up stand in Youngsville are stocking up for the Fourth of July holiday, sharing traditions that range from themed pickleball outfits to backyard pool parties.Michelle Billeaud and her husband operate the stand and have done so for several years."We always thought it'd be really cool to either do a Christmas tree stand or a fireworks stand to see what it was about just to have some extra money, and we always …