That's one of the things I love about the strat trem. If you want, you can bolt it down and forget about it, if trems and maintenance and screwdrivers and grease aren't your bag.
Or, you can spend all day thinking about it, spend hours tweaking swap out saddles, blocks, plates, screws, springs, strings and all combinations thereof, religiously worrying about how perfect you can make it and how clean and seamless and well maintained it is.
Haha. I thought that was a great idea. I don't know why, of all the improved strat trems (Floyd Rose, Wilkinson, etc) there has only been one to my knowledge that allows you to lock the bridge when you want to, and even then, that trem is pretty rare and difficult to get hold of (Wilkinson VS100CV).