Cremation is a hell of a lot cheaper, and it makes memorial services easier to arrange (unless everyone is hell-bent on seeing a plasticized body that is more haunting than anything).
Funny story - when my grandmother was diagnosed terminal with breast cancer and they were going over her burial wishes - she told my grandfather: "I want to be cremated."
"What? We can't do that."
"Well, it's three thousand dollars just to rent a casket, and it's not like any of us need it."
"... Okay... okay."
(This was the first time anyone in any of our involved families has requested cremation - but it's likely that my grandmother came to the conclusion after she saw how much one of her sisters' funerals cost).
"And then put my ashes in a two foot piece of three inch PVC..."
"What!? No, we can't put you in PVC, for Christ's sake!"
"Think about it! It's not going to rot, will last for hundreds of years..."
So, her ashes were buried in PVC pipe. Every family member, since, has opted for cremation - my uncle's ashes were scattered at his deer stand, my mother's and father's buried in ceramic containers (though PVC was entertained).
It was just hilarious how like my grandma her burial wishes were... the practical girl who grew up during the depression. I was truly blessed and am honored to have been raised under the influence of such a person.