Whilst it is probably true that the chances of anyone coming and demanding to see your Alcohol License are very limited, any organiser, worth his salt, would be foolish to ignore the requirement to obtain (or rather serve) a Temporary Event Notice. If anything was to happen at the event - anything - and the police were called to attend, then the crap would hit the fan. There would be a good chance of the venue not being allowed to obtain Temporary Event Notices involving sales of alcohol in the future - which would be very upsetting for the village hall committee, I imagine. As an organiser, your name would soon get very tarnished - and I think you could probably be prosecuted as an individual too.

In our area TENs only cost £21 - not sure if it is the same countrywide. It's not a fortune, and the costs can be offset from the money made on the bar. The altenative is, as has been mentioned above, to allow people to bring their own.