Can boiled linseed oil from hardware stores be used for oil painting applications or cleaning brushes?
Since you tagged this as oil-paint, I assume that is your intended use.

Actually, the BLO that is sold  in art stores is the same stuff that is peddled in hardware stores, be they large or small.

So you can use the BLO from the gallon cans for anything that you might use the BLO purchased from anywhere else.  

Edit:

Note that not all linseed oil is "boiled linseed oil".  BLO is not even actually boiled, but has additives that cause it to dry faster. Raw linseed oil is a slow drying product and may be refined.  Stand oil is heated and is lighter in color.  

Most hardware stores carry only BLO.  

Raw linseed oil is harder to find except in specialty stores (e.g. art supply houses).  Art stores are likely to carry multiple forms of linseed oil, but the one with the "Boiled linseed oil" label contains the same stuff as from the hardware stores.