A German friend is holding a BBQ tomorrow at which the Germany v. Australia World Cup match will be shown. On the invite was the request "Please bring your own meat to cook + condiment/buns + $5. We will provide drinks and salad for the $5." Likewise, at a German-hosted BBQ in Silicon Valley, a group of us non-Germans showed up to the BBQ, and then had to leave, go to the grocery store and buy our dinner, before returning.
At BBQs with Germans, normally everyone is expected to bring everything (meat, salad, chips, drinks) which they would want to consume.* This completely baffles me. BBQs are a chance to get together, share good food, and enjoy the companies of others. I understand keeping the costs/expectations for each guest to a reasonable amount by having everyone bring "normal" BBQ foods/drinks. So anyone wanting something extravavagant - like Champagne, or expensive - like a steak, or out of the norm - like gluten free/veggie burgers needs to bring them themselves. But otherwise, sharing is a good lesson to learn and a BBQ is a great place to practice sharing. With that said, I'm not a fan of the German BBQ approach as it doesn't promote sharing.
After my first German BBQ in Silicon Valley, my non-German friends and I made BBQ rules (for our BBQs) that everyone was expected to bring 1 drink or dish to share with the entire BBQ group. It was met with resistance at first, but over time I've learned that everyone actually appreciates it.
*Some of my German friends (usually those who've lived outside of Germany) now prefer the sharing approach to a BBQ (or so I've been told) and hold sharing BBQs.