It's fucking wrong.
Orator: says who?
The examples you gave are of games that an individual or small group invented. Those rules are therefore fixed on a time and place, and rigid. If you don't play by those rules, then arguably you are playing a different game. English grammar is not analogous as it was not invented by any such individual or board of governors, and noone presides over its so-called "rules."
As for the alleged rule of say, never ending a sentence on a preposition, the Victorian wanker to whom I referred was actually the 17th-century poet and dramatist John Dryden, and he invented the "rule" using material he found in his ass. There are numerous perfectly acceptable English phrases that necessarily end in prepositions, and there was a long tradition of ending sentences with prepositions before he ever made his claim. Here, you can read up on that one between turns of your bastardised games of monopoly or pool (and pay attention to the very important comment about adverbs, a common target of the hyper-corrective):
http://www.bartleby....4/C001/050.html
The consideration of adverbs technically disqualifies Churchill's famous rebuttal to the rule, but it's funny all the same. While that page cites no examples of awesomely famous sentences that end in prepositions, I invite you to read Hamlet's soliloquy on suicide. When deciding whether grammar ought to be descriptive or descriptive, I will side with Shakespeare over Dryden every time.
Starting a sentence with "but:" like I said, the "rule" is not to write a sentence fragment. Extrapolating from that that the word "but" cannot begin a sentence is derived from the unrealistic assumption that it is impossible to begin a sentence with a subordinate clause and then to end it with the main clause. This "rule" then is thrust upon every child from the first grade until the end of high school. The origin of this preposterous "rule" is unkown, but it is incorrect. It is in fact common to have a subordinate clause begin a compound sentence, and many subordinate clauses begin with "but." Grammaticalkly correct sentences beginning with "but" - sentences that would suffer the red ink of a traditional schoolteacher - re common. On a whim, I googled the Declaration of Independence and found that the final sentence of its second paragraph begins with "but." It is indeed a fragment of a sentence, possibly bringing the larger rule into question. How frequently do sentences not contain the full subject-verb-object structure? Frequently. Commonly when describing a series of events, as happens later in that same document.
The next paragraph begins with a common and correct sentence beginnig with "and:"
And while we're at it, the "passive" voice, frequently cast as an error in traditional grammar (you will get correction suggestions if you grammar check your sentences in Microsoft Word) is so far from being an erroneous "voice" that it approaches absurdity. The passive voice is in fact rather frequently necessary, and nut just to avoid responsivility as its opponents like to claim. It should be used when necessary.
If these things exist in writing, and have done so for centuries, who is it that is declaring them to be wrong? I know where you're going, Orator, with your attempted rebuttal fo the "common usage" argument: even a billion people can't make a word out of "irregardless" (or so goes the argument). But I am not even talking about common errors compounded by popularity. I am not talkjing about Faulkner's idiot-speech or Joyce's stream-of-consciousness. I am talking about commonplace and mainstream (ie non-experimental) writing styles that trace back to the origins of the written language. When I compare these with the alleged "rules" against them, I am forced to mention that some of these rules can be traced to individuals talking out of their asses and that others have no discernible origin at all.
Since we're listing things we hate, I suppose I hate what I am doing right now. By attacking the hated activity of internet pedantry, I am guilty of it myself.