well, you read the reason when its removed right ( rude or unproffisional ) most of the time its just removed because of an unproffisional way, manner approach, etc.
we are adults like u say, but some do not know how to control their temper or address each other in a proffisional way and they do that rather in a more aggressive / unproffisional way, if so, any MOD can remove that right away, not to leave it there for others to read and get more negative energy out of it.
in public forums its usually removed because someone praises other designer entry there, or try to draw attention to his own design, or even have a fight and pointing fingers to each other on the public forum, which is not why its there for.
if you had a good read through the designer code of conduct then you would know about all that.
so now you know, Moderators are not removing messages because its fun and they are bored, for fun, not like i get a need 4 speed chick poping out on my screen and shaking some
for me when i remove a comment.