Actually, they are probably arrow heads (archeology is one field in which scientists are mostly still professionals), and an expert can tell them apart from spear points, dart points, knives, or random rocks. These points are both too thin and too variable for atlatls, which require much more uniform points for useful accuracy. The hafting area on an arrow point is much narrower than on a hand-held or thrown projectile such as a spear or a dart (Why would any hunter/fighter use a hand or thrown weapon with a shaft as flimsy as that of an arrow? Someone so weak should be gathering roots and berries or working as a community organizer). Similarly, even the largest arrow points are thinner, lighter, and shorter than at least most of the smallest spear/dart tips. Finally, related articles describe impact damage to these points, and that is absolutely decisive. The types of impact cracks you get at stabbing/throwing velocities is different from that obtained through archery. These struck their targets at too high a speed to be spear points.
Also, there is a difference between a random rock and a tool that has been worked. More advanced weapon tips generally have both percussion flaking and pressure flaking on both sides to form the sharp edge, and this work forms a distinctive pattern. For the points in the picture, I see no sign of pressure flaking, but several show inexpert percussion flaking (comparable to my own workmanship when I have tried to duplicate the process). Random rocks don't show signs of having been hammered on the edge to chip a sharp edge. These points are not at an advanced level of skill, and I can't tell from this picture whether they were worked uniformly on both sides, but they have some of the same traits that you see on a Clovis point:
