If you're hitting sprite limits because you used up all the sprite slots, you're doing something wrong. Sprites are for moving objects that need to exist outside of grid alignment. For steady objects, put them in a background layer. If you need a different alignment than 8x8 tiles, you can use two overlapping layers to get 4-pixel horizontal alignment instead.
Absolutely! I think that's what the author meant when he said "In my prototype, your hand at the bottom of the screen is a background (similarly, in my E-Reader solitaire game, all of the cards are drawn into a background instead of using sprites)."