first aggressive note

I received this in my mailbox this evening, on a single printed sheet of paper:

Monsieur,

On nous a rapporté qu'à plusieurs reprises vous avez laissé le local à vélos ouvert, vous voudrez bien à l'avenir veillez à le refermer à clé systématiquement faute de quoi, nous nous verrons dans l'obligation de vous en interdire l'accès en remplaçant la serrure.
Pour info ce local n'est pas une prestation comprise dans votre contrat de location et que c'est à titre gracieux que la jouissance en est proposée aux locataires de l'immeuble et que si on continue à le laisser ouvert l'usage en sera restreint aux seuls propriétaires occupants et ce sans recours possible.
Comptant sur votre compréhension, votre civisme et votre respect d'autrui,

Le Conseil Syndical,

Which roughly translates to:

Sir,

It has been reported that on several occasions you left the bike room door open; you will in future be sure to close the door with the key, failing which we will be forced to deny access, replacing the lock.
For your information this room is not a benefit included in your rental contract, but is freely offered to tenants of the building, and that if you continue to leave it open, use will be limited to homeowning residents, without any possible recourse.
Counting on your understanding, your civic feeling, and respect for others,

The Building Council,

Now, I'm the last person to deny that I leave doors open. Sometimes even with the keys in them. I had thought that I'd been good about locking the bike shed, but it's quite possible that I haven't. I do wonder how people know it's me -- maybe because I'm one of only two people who uses the bike shed, as far as I can tell (more on that later). But this note seems to go a bit over the line. My actions, in their position, might be:

1. Put a sign up on the bike shed.
2. Wait, no, that was it -- problem solved.
3. Fine, hypothetically, I keep on forgetting. Then speak to me in person, or maybe put a note in my box, saying "You've been leaving the bike shed open. Please stop, or we'll have to bar access."
4. Ask me for my key back.
5. Upon my refusal, change the lock.
6. Upon further protests, point out that, as a tenant, I have no right to complain.
   

I am, frankly, baffled as to why step #1 wasn't followed, before #3+#6 was executed. I guess because they're French? I mean, honestly, what's the point of the second paragraph -- just a big "fuck you" to make sure I know my place?