To make the corpses stay?

I guess no ! Probably for a question of performance at the time the game was released.

Not just that. I have it on good authority from one of the game's developers that when they were beta-testing the game, their testers found that throwing around the bodies was a very easy way to eventually throw them out of the level boundaries somewhere and crash the game (and just the "fun" kind of move the players might try). No perma-corpses, no problem.

Interesting ! Thank you for the "off the record".

It was stated openly some years ago, on the now-defunct bloodrayne.co.uk forums. :)