Dispenser arrows can't damage mobs in minecarts

Steps to reproduce

1. Summon a minecart.
2. Summon a mob so it gets pulled into the minecart.
3. Place a dispenser so that it is pointed at the mob, from any direction.
4. Put arrows in the dispenser.
5. Activate the dispenser.

Expected result

Arrows shot by the dispenser hit the mob.

Actual result

Arrows shot by the dispenser pass through the mob and/or hit the minecart.

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Not sure if this is a bug but I see no reason for it to be an intended feature but while testing yesterday, I found it was impossible to damage mobs in minecarts using arrows that were chucked out of a dispenser, they either damage the minecarts, or go through the mob, this means it is a challenge to get a little bit of automation whilst dezombifying villagers