The comfort factor - anything over priced, expensive is thrilling. Currently it's wallpeper. And then when she buys it, well, it gives her such joy, fulfilment, contentent. Until she sees something else she wants to buy, then the cycle starts again.
Had a colleague like it with clothes. She bought new clothes practically every single lunchtime! When I sked her once why, her reply was 'there's just so many nice things that make me feel better when I buy them'. She never wore 90% of it either. A cycle of buying, returning, buying, returning continued for years. It's an illness actually. Said colleague went to counselling. Didn't help her sadly. The bottom line she was unhappily married and couldn't see her way out. I wonder if SJ's materialistic obsession stems from childhood??