It can also mean to overcharge someone, which is likely how it is used here. The exorbitant price of sacrificial animals is multiply attested. The poor couldn’t afford it

I’m not sure how your interpretation is meant to work out. I don’t see how people would be compelled to give their belongings to someone if the threat is directed towards random sacrificial animals. Are you trying to say that they were stealing from the sacrificial animals themselves, and that’s why he called them robbers? It doesn’t make any sense to me.