What actually runs behind the counter when you buy a bottle of wine? We trace the idealized merchant stack — payments, till, inventory, ledger, reorder, tax — from a one-person Jerusalem wine shop to a regional chain, and see how each rung simplifies, collapses, or papers over the layers. Along the way, we examine Israel's June 2026 mandate requiring real-time Tax Authority clearance for B2B invoices over 5,000 shekels — and how it's forcing digitization from the supply side before the sales side.