Re: What users want ...
"Donating to an OSS project is a fine and socially useful thing, but what that user WANTS is to get functional tools THIS MONTH, and directly paying for a commercial package is the only effective way to get that."
No, installing a package that has the functions is the only effective way, irrespective of whether that package is commercial or OSS.
The question arises as to what happens if there's no such package. For a start "this month" is unlikely.
If a mass-market commercial package doesn't do what you want you're probably not going to see that change unless you pay humungous amounts to the vendor because only the vendor can fix it and they have their roadmap for development so aren't going to be diverted for anything less.
Specialised commercial packages might be more responsive. I've worked with such vendors. Features could be requested but, of course, such packages tend to be at least semi-bespoke so they're probably nothing like as cheap as the mass-market package in the first place.
If the OSS package doesn't have it one approach would be to use its bug/feature requesting page to make a request. This might or might not work as some projects are more responsive than others. If the need is worth it you could pay a sufficiently experienced developer to add them. The cost is likely to be similar to that of the feature request for the semi-bespoke package but you don't have the up-front cost in the first place.