An illustration of what an Neolithic raid could have looked like. There is evidence of violence in the Neolithic period, one notable example is Poulnabrone portal tomb in Clare, one of the people found during excavations had a flint arrow head/projectile point in his hip, others had healed fractures.
I cant recall where I read it now, but I believe there was another Neolithic house that was found to be burned down and I think some arrowheads and the like found, which according to the account I read, could point to an attack of sorts (though alternative theories on Neolithic houses in general suggest to them being burnt down as part of a ritual at the end of a houses' life as well).
Personally, id say this kind of thing did happen, perhaps not as much as later periods when the landscape became more occupied and the struggle for resources intensified. But I would bet that some whose livelihood was lost because of one thing or another, may have decided to prey off of others to survive. Or perhaps there were those who made their entire existence off of it, cast outs. Its conjecture but probably then, as now, the biggest danger one had to worry about was other people.