Turns out we did still need InitSpriteTables.

pewpew.asm

@@ -59,6 +59,7 @@ Start:
     SetA8Bit
 
     jsr LoadPaletteAndTileData
+    jsr InitSpriteTables
     jsr InitWorld
 
     ; Set screen mode: 16x16 tiles for backgrounds, mode 1.
@@ -209,6 +210,25 @@ LoadPaletteAndTileData:
 
 
 
+InitSpriteTables:  ; TODO(mcmillen): why do we need this?
+    SetA16Bit
+
+    ldx #$0000
+    ; Fill sprite table 1.
+    lda #$01
+-
+    sta spriteTableStart, X
+    .rept 4
+        inx
+    .endr
+    cpx #spriteTable1Size
+    bne -
+
+    SetA8Bit
+    rts
+
+
+
 InitWorld:
     ; Start the background color as a dark blue.
     lda #4