The part with the respawn is using a loop, it's just a way to do something in few events and it makes the need of the placeholder sprites (and all the hustle arranging them) obsolete. It's not nothing necessary, although all those placeholder instances might add a few draw calls that tax the CPU a bit. But If the framerate is great, all is good
As for the web storage and Facebook stuff, I know nothing about these subjects yet, so I can't help unfortunately. I a m sure that there are tutorials for high scores though, try to search the tutorial section on the forum.