All I can say is, Aquarium Advice has come a lonnnnnngg way even from a few years ago!!
A topic like this one came up in the past and it was heated, hot, and unpleasant. Many members were fire-eyed and very outspoken when it came to the subject of what to do with your aquarium fish once they pass on.
Personally, I feel its a personal choice and every pet owner has their reasons and do what they do to help themselves best cope with the loss of a pet. If you flush, bury, cremate, preserve - thats your thing, then who am I to judge?
46 Gallon Bow F/W: 4 - Zebra Danio's, 2 - Red Platy's, 2 - lg. Silver Dollars, 1 - Pleco (4.5"), 1- Gourami, 1 - Cory Cat, 1 - mystery snail, 4 - Cherry Barbs, 1 - Black Molly