Pillager shoot WITHOUT targets

After an attack of pillagers patrol in a village, I typed "kill @e" with doMobSpawn in true.

Then I summoned a pillager in a cave and, the pillager started to shoot the stone wall(or the flower) WITHOUT A VILLAGER or someone else.

Another unreasonable point is, the pillager's arrows were bounced in the AIR

I'm sure that there wasn't any invisible villagers(as shown in the video), and the pillager had not been attacked before. I assume this is a bug in Village & Pillage.