The young Francesco, the future Padre Pio, wanted his crib scene to be as beautiful as possible. He also wished to light it up to make the scene as evocative as possible. At that time in Pietrelcina, there was no electricity and it was necessary to use oil lights. They had to be very small to enable Francesco to insert them in the moss, next to the tiny houses and beside the flocks of sheep.
The ingeniousness of the young boy was remarkable for those times. Francisco and his friends had learned to make lights made from snail shells. They would look for empty shells in the fields, clean them well, fill them with oil, add a wick and they would thus have a magnificent little lantern.
And so, of course the natural thing, out of all of St. Pio's incredible story, would be to entomb him in a resting place shaped like a giant snail made of stone and metal. That's what St. Pio would want that, right?
Some people are mad because the tomb is too glitzy. I personally think it is an outrage because of its obvious ugliness and ridiculous architecture. I mean, it is obviously hideous.
For pictures and links go to Rorate here: http://rorate-caeli.blogspot.com/2010/04/padres-pios-new-resting-place.html