Desperately seeking Lemon Drops?

It is Halloween and Albus forgot to pick up some sherbet lemons/ lemon drops while shopping at Honeydukes which is now closed for the holiday! In desperation he asks for help . Severus mentions that sometimes Muggle Candy Stores stay open. Both Severus and Minerva end up accompanying Albus and a horde of students on a 'field trip' to London to a warehouse filled with CANDY