Franking Credits, page-186

You are not clear whether you mean franking credits or franking credit refunds.
I will assume you mean refunds.
Franking credits were introduced to offset tax payable, they were never meant to be a cash refund to people who pay no tax.
However The Howard government changed that and added refunds as an electoral bribe to his retired supporters.
Now unfortunately that change has become entrenched.
It results in no tax being paid at all ie the company pays it and the government refunds it. A huge financial liability on the countries budget.
Ethically refunds should never have come into existence but as they are now almost impossible to remove I think it is most ethical to ensure the benefits are reasonably evenly spread. Not one person being entitled to a few hundred dollars worth and another being entitled to a few hundred thousand dollars worth. That's why I would support a cap on refunds and I suggested $50k as a reasonable amount because anyone getting more than that shouldn't need it and ethically should be happy to contribute back to the country that enabled them to become wealthy like Dick Smith says he would be happy to do.