The reasons of capital letters

Someone should explain me why on the bibliography of articles, books, reviews, every word of the titles of the references are written in all initial capital letters. There is no absolute, logic, understandable reason for that.

If a letter is capital it means that it is a personal noun: the noun of a city, of someone, of a place, of an important institution, of the Queen or whatever you like.

In German all the nouns start with a capital letter. In English the adjectives of nationality start with a capital letter. In Italian only  personal nouns. However strange these rules might be, they are the rules of the languages, established with time, with usage and maybe with some language reforms.

The capitals on the titles of references are totally another matter.

At the beginning I thought that I was going to desert this system. No, I would have not bended my knees in front of a pointless rule. I wrote all of my bibliography with only capital letters at the beginning of the titles and nothing more (except, of course, the other normal capital letters necessary in the English usage). I was proud of my self, of all of my short little letters nice and tight lined up on the pages. But I gave up. Cannot risk to be penalized only for principle. The principle of complaining about details.