Directed at any given individual, this would be a solid reminder of the post-capitalist society's realized liberation / empowerment, and unfettered access to the means of life and living (self-determination), for anyone.
*However*, there'd still be the material reality of 'not everyone will be self-contained / self-sufficient for their own needs'. A nominally-or-more *complex* economy will instantly mean that not all people are producing for their own consumption only, but rather that they are doing 'specialized' tasks, relative to those they are producing-for -- others.
While I myself abhor specialization, I still think that it would be inevitable in a post-capitalist society that has the *slightest* collective ambition, where it would benefit on the whole by *not* leaving everyone to do all requisite tasks evenly, as through steady rotations through all work roles.
So if such a society predominantly wants 'public transportation', such would require efforts from the granular, individual scale, towards the *collective*, overall general, *common* scale, while *not necessarily* obligating absolutely *everyone* to be an active participant towards the realization of this public-transportation-for-all.
In such an entirely realistic case, who would be the 'demanders', who would be the 'liberated-laborers', and who would be the 'consumers' -- ?
Working backwards, the answer for the latter would have to be 'potentially anyone and everyone would be consumers' since an egalitarian social order couldn't place arbitrary *conditions* for consumption on anyone, as with some kind of 'official' social status.
The 'liberated laborers' would have to receive *some* kind of commensurate social consideration for their 'specialized' efforts, since it's unlikely that *everyone*, to-the-person, would be evenly involved in just one-thing-at-a-time, like a public transportation project.
And the 'demanders' could be a critical-mass of overall public sentiment, enough to garner efforts that yield policy proposals, 'buy-in' over vast geographic terrain, volunteers, etc. -- but they wouldn't necessarily, automatically also be *liberated laborers* and/or *consumers*.
So, to conclude, there *is* / would-be a realistic 'operational' 'disjuncture' among the various socio-material roles in a post-capitalist society -- the original thread topic is *valid*, in asking 'how to manage [material] supply and demand' within this kind of social context.