I’m the current Head of Business Operations at 80,000 Hours.
Before that I was the Interim Head of Operations at the Centre for Effective Altruism (CEA), where I also was previously the lead organiser for EA Global. Before working at CEA I was an Operations Assistant at Open Philanthropy, and prior to that was involved in various community building projects at EA Oxford.
It depends on the venue, but for EAG Boston for example the food and beverage minimum spend is $540k, and we’re planning to spend just a bit over this (we may go higher if more attendees end up registering).
I’m not sure how those academic conferences work — it’s possible that they take place in venues without in-house caterers or that they pay more up front to avoid a minimum spend. Because we usually get a minimum spend, attendees aren’t allowed to bring in their own food unless they have serious allergies (though of course people might still bring in their own food covertly).