making independent art isn’t cheap, easy, quick or often valued in any material sense (further reading). contemporary art, media, and cultural work is often unstable and precarious at best, so your support is appreciated and goes towards paying off debt from the costs of:

• equipment: photo quality printers, shipping labels and label printers, sticker cutters, art & design software monthly fees, web and online store hosting fees, frequent equipment repairs & replacements, required upgrades, etc.
• supplies: ink and toner cartridges, matte poster papers, sticker papers, recycled zine papers, shipping mailers, boxes, envelopes, and packaging, etc.
• overhead: physical workspace for supplies and equipment to be organized and utilized, travel costs to repair or acquire equipment, wear and tear, utilized (electricity, wifi..) etc.
• labor: paying a living wage for the energy and time given – not only to creating the art itself – but to the many trials and errors that are made and fixed in order to get to a final print piece of art 

and after all that, if there's anything left over to pay for the others costs of living, your support allows artists to "buy the time" to work on and participate in other creative, organizing, and/or educational projects.