Yes good idea to which I would go one step further and ask the school that in fairness and balance if they are going to do meat free days they should do meat only days.Its Propaganda, plain and simple. That has no place in a school in any form.
That's a simple argument to make to any head master/mistress to get it removed.
This obviously will be met with howls of protest due to not allowing the non meat eating staff and pupils a meal. At which point you say ah well......