I think this is a bit of a fallacy. There was plenty invented in pre farming times, just these inventions were tailored to the task at hand which was hunting and foraging rather than other goals. For instance, the spear thrower. With that invention the act of spear hunting became orders of magnitude easier for less able bodied people. Spear throwers can be used to send a projectile 100m, and as fast as an MLB pitcher. You can imagine how this might have significantly improved the kill rates of the hunt, and could be thought of as significant of an invention as perhaps the plow was.

> if you're constantly following 4 legged food.

This is such a weirdly persistent bizzaro notion of hunter-gather lifestyles.

I grew up in the Kimberley region surrounded by and outnumbered by traditional hunter gathers ( some sea | some river | and we'd move south and interact with some of desert folk ) who had their food for the day in hand in under six hours, easily.

It makes more sense to think of Hunter-gathers as quasi nomadic across an estate that reaches to the horizon and beyond filled with animals they watch and both eat and protect, along with edible plants they harvest and encourage (by churning up soil and throwing seeds and husks back into).

The days are filled with story telling and walking a circuit looking for fresh tracks, hacking a few thick plants, digging out roots, sifting low tide mud for molluscs, pinging a few lizards in the head with rocks from a basketball court distance away, etc.

Hunter-Gatherers do practice agriculture, it just doesn't look like western european agriculture, more like ripping out 'bad' plants and spreading the seeds of good plants.

There's plenty of free time.