Go to any burger joint or hot dog stand and you’ll find a collection of bottles, often corralled onto a tray, usually including ketchup, mustard, relish, mayo, hot sauce, and BBQ sauce. If French fries are also on the menu, maybe there’s salt and pepper nearby. Sometimes, they’re found in squeeze bottles that can be used to drizzle ketchup on fries or zig-zag mustard over a hot dog. Other times, they’re in a more centralized location where customers help themselves and go, likely struggling to…