Our dojo does them when its called for. If you get caught doing it when it isn't, or are jumping into a breakfall, you can get scolded.
No need to slam your body around unless its called for. Sometimes if I get behind as uke or due to the power, I take breakfalls. I am working on making them softer, but I haven't gotten there yet.
I guess the exception would be if you were working on breakfalls.... then you have to take them.