Um, congratulations? Thank you for sharing? You deserve an award for being such an upstanding citizen? Oh no, we have seen the error of our ways, thank you for sharing your wisdom on how not to get banned in the first place?
Sorry, I'm just not sure what response you were looking for there.
In the meantime, the use for LocalFriendCodeSeed injection should be obvious: people don't want to be banned. Injecting these can unban us. Sure, the public seeds will inevitably get banned, but then another one will take its place, and banned players can resume. And to the best of our knowledge, private seeds could last indefinitely, barring some yet unrevealed method of detection.
My o3ds was hit in the so-called "banwave" a couple months back. I have used LFCS injection to circumvent it. Am I entitled to Nintendo's online services? Nope. Do I have an unconditional right to play my games online? Absolutely not. As far as I am concerned, Nintendo acted completely correctly in banning my system, as even though I use it for purposes I view as innocuous (ROM hacks, custom themes, save backups, etc., never cheating online or even trading/battling with hacked Pokemon), I knew the rules against 3DS hacking, and I knowingly broke them. Revoking my access was the correct course of action.
I didn't unban my system because I thought I was banned unjustly. I unbanned my system because I could, because I wanted to, and because I could get away with it. I did it because even thought I'm not following the rules, I'm also not hurting anyone or disrupting anyone's online experience; in other words, unbanning myself is not harming anyone else.
And I did it because I couldn't access the Pokemon Bank otherwise.