Stock traders don't "provide" anything, they're just playing a part in a poor, and exploitation-buttressing, system of exchange and resource allocation.

That's a very shortsighted view.

Shortsightedness is exactly the problem with daytrading.

Well don't daytrade if you're shortsighted, for sure. But if you think daytraders can afford to be shortsighted, you're very wrong - it's one of the most exposed professions in this regard, the market will react weeks or months in anticipation of an event.