Hi Kestas,
These fasteners are not temper-proof, but merely temper-resistant. They are supposed to keep the layman, who doesn't know what this type of fastener is, from casually tinkering with things. For example, on public buses, exposed fasteners on grab bars and handrails are frequently of the tamper-resistant variety, because otherwise bored schoolkids may loosen the fasteners. I have often observed kids picking at those fasteners, and I have yet to see one produce a proper tool for removal. On personal vehicles, there is equipment the layman is not supposed to play with. The person who knows what tool to use to properly remove the fasteners is probably not a layman and will have no problem removing the fastener in question, and installing it later properly. Ironically, any idiot is allowed to loosen lug nuts and wheel bolts and tighten them as improperly as he wishes.
Cheers,
-J