Flipping your cards when you close out action strikes again

Long story short: My wife's relatives from Florida are staying with us for the foreseeable future, attempting to ride out the hurricane.  They live in Miami, 4 blocks from the beach, in a place that at this point is likely now consider "beach front" - if not "in the ocean" - property.  The last time they stayed with us was over 7 years ago, where I wrote about him in a post from a home game that I held.  In the 7 years since he's been to our house, Maryland has legalized poker & gambling, and 3 ensuing casinos have opened within a 45 minute trip from my home.  Saturday night, I took him to go check out the MGM Grand in National Harbor.

I was card dead for most of the night.  I ran a bad bluff where the short of it is that my opponent looked me up with KTo on a King high board, but I basically walked away break-even for the session.  Close to the end of the session, I get moved to my wife's cousin's table because my table broke.  The open seat is on his left, good spot because I know he's pretty recklessly aggressive.  True to form, he's betting and raising.  Mixing it up pretty good, and definitely hitting his cards.  I'm seeing a bunch of questionable plays, but he seems to be scooping pretty consistently.

DISCLAIMER: I'm not particularly proud of the following, because there's some questionable activities below by me, mainly violating the "one player per hand" rule.  Still, it's worthy of writing a blog post despite my violation of the rule.

I've been playing at the new table for around an hour when an early position (EP) player raises to $12 (1/3 game).  It gets called in 2 spots and my wife's cousin (WC) 3bets to $30.  I haven't seen him 3bet, but I've seen him raise somewhat often.  Regardless, it's a small raise compared to the pot size of $36 + $12 = $48 before the $18 raise.  All players call and I fold 56o.

Flop comes 3 4 T and I think original raiser leads for $~40(????).  I wasn't paying very close attention until the river, unfortunately.  The cbet clears out the cold callers who fold, and WC just calls.  Turn is a 2 which would have been my nut card(!!!!!).  I think it checks through.  River is a 7 which would have given me up & down, but original raiser leads for all in (approximately $240).  His bet is an overbet; not huge, but the bet feels enormous given the action.  WC looks at me and whispers, "What should I do?" as he shows me pocket Queens.  My first reaction is to shrug and mime "no clue."  Then, as WC starts to tank, I whisper to him: "flip your cards up and see what happens."  I know full well that the casino rule is to disallow overturned cards, but nothing will happen except a warning and a "stern talking-to," and not to do it again "or else!"  He listens to my advice and flips up the Queens, much to the chagrin of the dealer who scolds him not to do that.  However, the damage is done - the cat's out of the bag - the horse has left the barn - whatever other cliches you can think of.  The reaction on his opponent's face is priceless; it's all in the eyes... his reaction is almost as audible as a groan, but this is a 100% genuine reaction.  His eyes flutter and look up in disbelief, signaling that he knows he's in trouble.

WC calls pretty quickly after turning his cards back over such that they're no longer exposed.  After 10 seconds, WC throws in chips for the call and flips up his QQ for the win.  The dealer starts pooling the bet into the main pot and his opponent starts getting loud.  He contests the pot, saying that the rules were broken, and WC should forfeit his hand since his cards were exposed before action was closed.  He's holding onto any thread of hope that the pot can be returned to him, but to no avail.  Floor comes over, instructs the dealer to ship the pot to WC and a 10 minute discussion by floor and the opponent continues about how what's the point of a rule if it's not enforced, etc.  However, pot is awarded and we rack up to leave at 3 a.m.

To be honest, it is a pretty dumb rule; if I want to flip my hand over at any point throughout, why can't I?  Obviously, one could argue that I gain an unfair information advantage by getting the reaction, but one could argue the opposite: if I incorrectly [or even correctly] fold, my opponent now knows that he/she can push me off of hands of that particular strength in the future.  More to the point, if this hand flipping rule is in effect, what is the actual penalty?  Is there a difference between accidentally exposed cards vs. purposely?  Because the penalty should be the same regardless, just like an accidental string bet that seems to be very strictly enforced as a string bet, or acting out of turn accidentally.