It's well established that poorer people not only have fewer resources, but are generally worse at allocating the resources they do have. This is attributed to a difference in perception of money (something to spend vs something to save).
It's not a difference between being able to purchase an item versus not being able to. It's a difference between being able to invest heavily in each item you own — certainly a privilege of the well off.
In any case, whether the loudest advocates of minimalism are annoying or not, our base level of consumption is far too high for a variety of reasons: environmental, economic, and yes, I think emotional.
There are immense resources poured into making people want/need/desire more "things," and if their ability to acquire "things" doesn't make that possible, there's an inherent damage to a person's psyche.