I have never been to Roka but I am prepared to accept the MANY positive reviews and comments from people who are regular on this forum and have been for years. I can imagine any one of your complaints being true (well actually, I can't for a minute think they gave you margerine rather than butter) - but it is totally unlikely that EVERY part of BOTH your meals was shoddy. Your contributions here have only been negative comments about restaurants, so you don't come across as the most balanced of reviewers! Dozens of individuals praising this restaurant or one new member turning up out of the blue and claiming that every last thing was below acceptable standard, hang on it's a hard one to weight up...ah yes...
In short, it isn't that negative comments are not well received here, it's the fact that I simply don't believe you.