If you don't assign anything to the Pic* pointers, then no memory will be used. If you need a large amount of sprites, you can put them all under the same pointer and index them, since they are all 8 bytes. For example:
[the hex for your first sprite here]→Pic0
[the hex for your second sprite here]
[the hex for your third sprite here]
[and so on]
Now Pic0 is the first sprite, Pic0+8 is the second sprite, Pic0+16 is the third, etc.
This trick is very useful if you need to manage a large number of sprites in an enemy system, as you can just draw any of them with Pt-On(x,y,I*8+Pic0), where I is the enemy's number or whatever else you decide. Also great for tilemapping.

It does not save you memory as the actual data is the same size.

How much data are you using? Even 80 sprites can fit inside L1. If you have massive amounts, you can store the sprites in an appv and copy it to ram when the program runs. I have never run into trouble with the amount of sprites. I usually run out of ram.

Do what I told you, it's the best way to do it. Also remember that you can have custom named pointers with °.