Your choice! We like to stick with vegetarian food because everyone can eat it and it keeps costs down. Healthy snacks are great because they prevent that post-meetup regret when you realize you've just eaten six pieces of pizza.
Our one rule is we don’t pay for alcohol. We’d rather spend the money on hardware.
If you follow the laws in your country and stay safe, it’s fine if you BYOB (bring your own beer).
You can find a list of great snack options here.