We treat payroll as zero emissions. The responsibility boundary of a company doesn't include the personal consumption decisions of employees. The spend-based approach makes this pretty straightforward — if the company is buying, those are company emissions. If an individual is buying, those are individual emissions.
Not trying to put you in a 'gotcha' situation, but GHGP Scope 3 Category 7 (Employee Commuting) is entirely related to employee actions outside the bounds of the company. Commutes and also home-office energy choices (heating, cooling, use of renewable energy credits, ...) are typically chosen (and paid for) by individuals outside of work but are components of an organization's value chain.
ya, that's right, good point. For complete GHGP inventory reporting, customers need to estimate employee commuting separately (and we're happy to help with that; it's usually a pretty straightforward calculation, though gathering the employee info takes some doing).
Setting the GHGP aside, my own personal opinion about how we interpret GHGP data is that it's important to make a clear distinction between upstream emissions and downstream emissions. For example, 'use of sold products' (Category 11) is also not something you can determine from spend data. But I'd argue that 'use of sold products' is a very different thing than upstream emissions (even though they're all lumped under Scope 3).
Commuting is a less clear-cut case, but I think of commuting (that is paid for by employees) as more of a downstream emissions category.
