PST lower control arm pivot shaft, dimpled bolt question.

Im installing the pst lower control arm bushings and pivot shafts. As you can see in the pictures the bolts provided have three indentations on them. These stop the bolts from threading on easily by hand, when you use a wrench to tighten the bolts these dimples sort of lower the height of the threads.
Is this so the bolt will not become undone? Seems like it would be better to just use loctite since this ruins the threads? Thanks!

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