Anonymous donors gift gold coins to the Salvation Army:
http://wcluradio.com/kentucky-donor-gives-1-3k-gold-coin-to-salvation-army/
https://www.wxyz.com/news/secret-santa-drops-gold-coin-worth-1-300-into-salvation-army-red-kettle-in-st-clair-shores
https://chicago.suntimes.com/news/gold-coin-salvation-army/
Apparently one generous guy has been doing it annually since 2013.