They reacted that way because that particular stage is Hilde's greatest boon, where just one charge of C2-3b or C3a is all it takes to win. Nightmare's RO game is strong, but if it were anywhere near Hilde's, rest assured that people would be reacting the same way.
First above all: Nightmare and a lot of characters famous for do stupid RO in SC3 were nerfed in their RO properties. Hilda has a stupid RO power comparing to the others (except for Kilik, Amy and Algol who does stupid ROs too, but not from so far)... And for the boo thing, there's not player who deserve to be boo...
Damn, that had to be the most evilest "BOOOOO" from the crowd when Ceirnian won the first match... and why is everyone bitching about the stage selects... nobody bitches when it's an open field with Nightmare... bunch of babies o_O.
