That is absolutely horrible! GamesCom is hard work and a great opportunity to show what actual blood sweat and tears have managed to conjure up for many solo devs or small teams in the indie space :(
Quick question for clarification tho - area 4 here is business only - the actual indie booths are in 10.2. Hall 4 is not even open to the public. If the raid was indeed executed in hall 4, then some low life might have thought they are "just bleeding greedy Corporation assets". Theft is despicable either way tho, sorry to read this :(