Here's a simple truth: if you are manually building 500,000 store-and-item rows one by one, you are doing work that a machine should be doing for you. The Reddit user who posted this question knows exactly how tedious this is, 100 items, 5,000 store locations, and the need to generate every possible combination in its own row. That is half a million rows of data. No one should spend days copying, pasting, and dragging formulas to create a list that any modern tool can assemble in seconds.
The instinct to ask about a macro is understandable. Excel has been the default for this kind of task for decades, and macros can indeed automate repetitive work. But here is what that approach misses: a macro is still a workaround for a tool that was never designed to think for you. You write the VBA code, test it, debug it, and then run it, only to end up with static data that still needs to be validated, formatted, and updated the next time your inventory changes. The problem hasn't been solved; it has just been automated into a different kind of manual labor.
An AI-native spreadsheet flips this entirely. Instead of writing a macro, you describe what you need in plain language: "Combine every store with every item and output each pair in its own row." The system understands the relational logic, executes the cross-join instantly, and delivers the result as a live, editable table. When you add a new item or a new store next week, the output updates automatically. No code, no debugging, no wasted afternoons. The transformation is not just about speed, it is about rethinking what a spreadsheet can do when it understands your intent rather than just your formulas.
This is the practical shift that matters most. The user's question is not really about macros; it is about escaping the burden of repetitive, error-prone data work. The solution is not a better version of the old method, it is a fundamentally smarter tool that removes the friction entirely. For anyone managing thousands of rows and dozens of variables, the question should no longer be "How do I automate this in Excel?" It should be "Why am I still doing this manually?" The answer is waiting in a tool that treats your data like a conversation, not a chore.