An audience of more than 500 came out Thursday evening for "A Home for the Holidays," a benefit concert by two groups of Amazon employees — the musicians of Amazon Symphony Orchestra and the singers of Vocally Self Critical. Between ticket sales and additional donations made by concertgoers, the event raised more than $18,000 for Mary's Place, the nonprofit that operates shelters for homeless families, including one that will be housed in a building under construction at our Seattle headquarters.