i have to admit this really grates on me too.
our office is open plan (a massive large room, so noisy enough as it is, with people talking, on the phone, printer noises). there are so many people here eating and making clinking noises at lunchtime that i've taken to arranging conference calls before 11am and then after 3pm, it's that bad.
seriously, the woman to my left eats early, she goes for sandwichs and a coffee at 11am, rustles the wrappings/slurps, etc.
then the guy to my right goes and gets his packed lunch at 12, normally it's crisps, so crunch crunch crunch
later on the soup people get their lunch out, so the microwave (at the side of the room
) pings, and there's the clinking of the bowls
It honestly drives me mad, and will be one of the criteria i'm adding to my next job: somewhere people can eat their lunch in peace, and somewhere people can get on with their jobs.
because it's not like i can just avoid doing work in that massive 4hr window, right? so i have to arrange my working life around the shitty open office design.
i have no idea how nice it was to have my own office in my last job. here, everyone, no matter what level, is in this open plan room, and it's a huge issue for me.
so no i don't think your colleague was BU. your soup bowl may just be the final straw in a wider issue (poor office planning for the type of office work you're doing e.g. like me, who has to take 3 or 4 conference calls a day, usually with non-native English speakers, so I have to speak clearly and listen intently)