The strongest complaint you can make is presumably "I wouldn't have come if I knew a team like this could enter and even win, and I won't come to your next one, and I will be sure to let others know that I won't come and why". Saying it publicly with all the other entrants around lets others join in if this is something that is widely regarded as unpopular and lets the organisers know that there is some serious resentment. Not complaining at all is certainly one way to make sure nothing will be done.
I mean, nobody here can even say "wow, I won't go to their next one!" because you haven't even named them.
I mean, nobody here can even say "wow, I won't go to their next one!" because you haven't even named them.