In the anarcho-mutualism a minority of anarchists advocate (I prefer anarcho-communism) people would still have to work (usually making things to sell on the market) but workers would have control over their own workplaces. In addition, there would no longer be any capitalist exploiting the workers and as a result we would not have these massive wealth inequalities and workers would be richer (they can keep the surplus value which is normally extracted from them). This would be a substantial improvement over the status quo.
In Anarcho-Communism, factories and other things would be produced either because people need them or because they enjoy producing them (or both). To produce a new building or factory or whatever, those interested in doing so can come together, organize (non-hierarchically) and build it. The Spanish Revolution shows that capitalism is not necessary to build new factories. To take one example:
"If by industry is meant a group of manufacturing establishments making the same type of merchandise in a county, province, or region, then there was no optical industry in Spain before the 19th of July....
.... The greatest innovation was the construction of a new factory for optical apparatuses and instruments. The whole operation was financed by the voluntary contributions of the workers. In a short time the factory turned out opera glasses, telemeters, binoculars, surveying instruments, industrial glassware in different colors, and certain scientific instruments. (The workers presented Buenaventura Durruti with a special set of field glasses.) Another achievement was the opening of a new, up-to-date optical school.... The workers had every reason to be proud of these achievements. What private capitalists failed to do was accomplished by the creative capacity of the members of the Optical Workers' Union of the CNT." - Augustin Souchy and P. Folgare (eds.), "The Collectivization of the Optical Industry," in Sam Dolgoff (ed.), The Anarchist Collectives, ch. 7
See
here for more on this subject.
The reward for producing things would be both the enjoyment of doing it and also the results of that production - be they glasses, food, or whatever.
Work should be abolished. The "reward" the capitalist gets for starting up new businesses, investments, etc has nothing to do with "incentive" or "risk" but is exploited from the workers. The capitalists have a monopoly on the means of production; the only reason an "incentive" is required is because they will use their power over the means of production to prevent anyone from producing unless they get the lion's share of the wealth. Break that monopoly, establish self-management, and paying a bribe to the capitalists is no longer needed for production.
Where possible society should be organized so as to reduce those unpleasant tasks (cleaning sewers, etc.) as much as possible. This includes the use of automation, reducing reliance upon those tasks, reorganizing the economy to be more efficient, etc. Any unpleasant tasks that cannot be completely eliminated should be shared equally. Making a few do it all the time while the rest of us do more fun things is unfair. The present system compounds that unfairness by paying those who do these unpleasant jobs much less than those who do more pleasant things (like acting or playing baseball). If the capitalist nonsense about "incentive" had any bearing on reality (other than that of contradiction) then famous actors would be paid very little while sewer workers would be paid a fortune, which is not how real-life capitalism actually works.
Site Feed