Originally Posted by
Moe Zhoost
Assuming the OP has found the leak, which probably was caused by a small piece of road wire, there is no reason to replace it. A quality patch system, like Rema TipTop, will give a permanent fix. Why contribute to filling our limited landfills?
Do you really think that a pressurized tube can move within a tire? 
I consider Jobst Brandt to be the final word on most things related to bikes. He claims that
talc is of no benefit and may actually cause air to be released more quickly from the tire in the case of a puncture.
totally agree on patching and not wasting resources, but as for creeping tubes, it's very common when people never add air to tires and ride with very low pressures. Common to see awkwardly slanting valves, tube creep. I've dealt with it with friends bikes numerous times --"sure I add air to my tires, I did it about 6 months ago, what? What? Every few weeks? This tire feels fine to me, thumb pinch" (tire at 25psi, should be at least 60)
caveat, I'm new to fatbiking, so I'm very curious to see how low pressures with fattubes goes for me. Previous low pressure stuff has only been up to 2.5 in tires, winter riding, with no problems, pinch flats nor tube creep. Can't recall pressures, would lower for snow conditions by feel, I suspect 20 psi ish. Light rider though and not jumping off curbs etc.