Yau

to me, gender is the weirdest invention. They're inconsistent in many cases, and gives no any meaning about the vocab. I never know why a table is "la" word, instead of "le", but parfum is "le". All they give us is a burden.

Tense (i mean conjugation) is not necessary to me too. We have a word like "aujourd'hui" or "yesterday", what's the point of having so many conjugations to indicate different state of time? It seems to me that there's more convenient way to express a mood or time than using conjugated verbs.

I may be wrong. Please share your thoughts. What is the weirdest inventions in language to you? Characters? Articles?

mansio

Why don't people wear the same clothes the world over?

It is the same with languages. Every people or group of peoples has chosen a certain way to express things and it may be different from the neighbor's.
Variety is a result of man's intelligence.

Genders are not "an invention". They follow rules although some may have been forgotten.
Table is feminine for two reasons: the "e" (a later evolution of the "a") denotes mostly feminine words in French, and the word comes from Latin tabula where it is also feminine.