What do you use the flint for, exactly?
Do you shoot the tree down with arrows, or light it on fire?
Im sorry, maybe i have to be more specific to some ppl without imagination or basic logic power:
Flint, can be used to chop the wood instead of an axe
What's the logic behind this? Well, as far as i know humanity started without axes and tree punching magic fists, so.. Flint, its common and hard enough to use it as a tool
As we all know (maybe you don't) stronger materials can be used to destroy/cut/pierce/etc.. materials, so flint, being easily obtainable in game at first, being hard enough to help getting wood, is a good thing to take down a tree
And nope, i first need wood to get the arrows (at least if you don't kill a skeleton) and.. Nah, lighting on fire? I want wood, not ashes
As frankenstein said: Fire! BAD!
And, sincerely man, you really need to open your mind a little, you're really confusing real world reality with minecraft, you need to think more as a human and less like steve.. Or you will end up punching a tree if you find yourself lost in the woods.. And i wouldn't like to be you that day, ouch :/