Once, I booked a registration at an AA event, which included meals. They published the offer online; I accepted the offer online and paid; and then, a few months later, they contacted me to say that they had mispriced the meals and that I would need to pay more—quite a lot more—to have the meals and that they would not offer a refund. I remonstrated (politely and in a measured way), but they demurred.
Now, this approach is quite wrong: If, after a contract is concluded, one side wants to vary the terms, this must be agreed; if one side does not want to accept the change, the party requesting the change must fulfil the contract as contracted for; the only available remedy is rescission of part or all of the contract (i.e. unwinding the whole thing back to the status quo ante).
This particular AA event was not actually labelled an AA event. It was billed as being for AAs and having AA participation, but it did not hold itself out to be sponsored by the fellowship of AA. Quite right! For an event to operate in that way would besmirch the reputation of AA were it to be held out to be an AA event. As it is, the only reputation that is besmirched is that of the particular committee in question.
However, were the event sponsored by the AA fellowship, it would be financially and operationally accountable to the fellowship, e.g. an Intergroup, Region, District, Area, etc., and the above situation would have been resolved differently.
If attendees had objected to the unlawful attempt to vary the contract, they could appeal under Concept V to the higher authority, namely the sponsoring Intergroup, Region, etc., which, being composed of AA members who are distinct and detached from the committee officers, would be able to assess the situation neutrally. It is very likely that the sponsoring entity would have suggested that the event absorb the costs or that it would offer a refund to those unwilling to pay more.
A good sponsoring entity would have been available to consult on questions like this, under Concept III, which might have avoided the unlawful offer going out to attendees in the first place.
The sponsoring entity, if it was doing its job, would have ensured that the event itself had its own ring-fenced prudent reserve to cover such eventualities.
The sponsoring entity might have simply bailed out the event with AA monies for the sake of preserving reputation and good faith, fair treatment of attendees, avoiding public controversy (Concept XII), and wrangling about money (Tradition VI, maintaining unity (Tradition I).
Finally, if the sponsoring entity concluded that the committee was not fit to make appropriate decisions on this scale, and no amount of censure or redirection could fix this, it could reorganise or replace the committee (Concept II, Concept III, Concept VI, Concept VII).
For the above reasons, whatever the legitimate reasons for holding an event outside the structure, the gold standard is to have the event sponsored operationally and financially within the fellowship.