Is there anything hugely difficult about organising an event if the venue provides catering?

I used to do some work for a local branch of the National Union of Teachers and one of the roles included organising training events. We provided a meal during training days and snacks for other events, such as, meetings after school.

To ensure that everyone was catered for, and so we were aware of allergies, I'd ask those who registered, if they had any dietary requirements. Unfortunately, sometimes I'd wished I hadn't!