The reason "marketer" seems so common is because those who are good at marketing are inherently good self promotors. Making them far more visible than other, less common examples.

Anecdotally, supply chain and business operations are two big areas where I have success.

You don't even really need any domain knowledge to get started in those fields. I did a 6 month internship at one of the world's largest companies that has a consistently top ranked supply chain organization. They had the expense of a 10 person recruiting team (all expensive line managers and directors, not HR personnel) coming to campus for 3 days, and only gave offers to two of us. And I explicitly said during my interview I knew jack all about supply chain. Their response was that supply chain was their expertise and they had training for that if I needed it, but my general analytical skills and Excel knowledge were far more rare (in their applicants).

Turns out they were piloting a new inventory management methodology and were using Excel-based "models" to trial it manually at a dozen manufacturing plants before deciding if it was worth the 8- or 9- figure cost to have SAP make that an official model in their system. It involved running batch exports from SAP every morning, putting that into Excel, updating the figures, and sending that out to the plants. But the pilot had scaled to a high volume plant that basically maxed out Excel, and they were struggling to make it work. All I did was essentially refactor a lot of logic to do batch operations (made a few VBA scripts that connected to the Excel spreadsheet with an ODBC connection and ran a series of SQL statements instead of in-cell functions).

It's been about 5 years since then, and I still get calls every few months for contract work essentially doing the same thing (Excel got bogged down -> needs a refactor).

Part of my day job involves essentially doing the same thing, but in a more generalistic sense on business operations. Process engineering is a portable skillset across verticals. Whether it's in supply chain, sales, marketing, or operations, there's always a bottleneck that's preventing growth or efficient resource utilization. I am a piss-poor programmer. I have never once been hired or paid explicitly to program, and I don't have enough experience in any particular language to pass even a junior level programming interview. I get paid to make irritations or problems go away while causing the least amount of friction utilizing whatever constraints exist. In the course of doing so I've tweaked C# and PHP programs. I've written bash, awk, perl, VBA, Python, and NodeJS scripts. I've written a whole lot of SQL. And I've refactored an incredible number of Google Sheets and Excel workbooks. I'm not valuable because I can program; I'm valuable because I can reliably and consistently resolve whatever issue is thrown my way in a self-sufficient manner, and ramp up on whatever knowledge or tool is needed to do so incredibly quickly whether I have prior exposure or not. I'm not a consultant that provides a report that then requires additional resources to execute; I provide a working solution (or prototype) that immediately solves the issue. And in the case of a prototype, provides a stopgap solution that (crudely) solves things in the immediate term and provides an explicit, working example of the functionality that their engineering resources need to incorporate into their internal tools/processes for a long term fix.

One piece of advice that seems to serve me well: people hate change. And people also tend to hate relying on others to perform their job. The greater the change, or the more reliance on a programmer to make modest changes to a process, the more resistance and ill will you'll create. Engineers thrive for perfection, and invariably lean towards "optimal" solutions that are very invasive and supplant existing practices, rather than supplementing them. patio11 didn't create an entire Customer Management System or appointment management system that had automated appointment reminder functionality. He created a simple system that supplemented whatever process and system was already in place and added incredible benefits with minimal additional steps.