How does Janis Elspas's method for creating a Christmas tree out of shopping carts outperform traditional designs?

I don’t actually have a detailed step‑by‑step “method” from Janis Elspas for building that shopping‑cart Christmas tree, but I can speak to how a design like that can outperform traditional trees.

A giant tree made of shopping carts is:

1. Visually dramatic and highly shareable on social media
2. Memorable for malls, arts centers, and public spaces
3. Reusable and eco‑friendly, since it repurposes existing carts
4. Strongly branded as pop art, tying décor to place and experience

Would you like ideas on how to recreate a similar cart-tree safely for a store or event?