If I got drunk, wandered in to your house and took a nap on your sofa, would that be a property rights violation IYO? I really don't think I should have to explain why this type of thing is "a violent act", or that if you argue this point anyone should take anything you say seriously.
You are begging the question that people have rights to property. So let's rephrase: If you got drunk, wandered into my house, took a nap on my sofa, woke up, and left, and I never knew, would that be a violent act? IMO no it would not be as no one was harmed and no one was fouled. You got a good night sleep and I didn't care.
If people don't have rights to property they cannot survive. All organisms are subject to the 2nd Law of Thermodynamics, that is that the entropy of an open system is always increasing. In order to counteract this, organisms must decrease entropy locally by controlling and consuming resourcs around them. Ownership of property is simply the economic controll of resources, and fundamentally, energy, and the ability to utilize said resources in order to sustain oneself. This is the basis of property rights.
For an insightful look at property without resort to the arbitrary constructs of "God-given" or "Natural" rights, read Butler Schafer's excellent book entitled "Boundaries of Order". Free online in PDF form.