fees - Why don't most academic conferences make their budget publicly available?

I wonder why most academic conferences don't make their budget publicly available.

Making budgets publicly available could help explain high conference fees (which attendees often complain about), help other conference organizers, receive feedback to be able to improve, improve transparency towards the taxpayers since they fund most of academic research, explicitly mention what the private sponsors are and to what extent they are involved (e.g. to detect conflict of interests), etc.