It's intending to obscure the capitalist relation. The farmer is petty bourgeois (and practically non-existent, agriculture in many countries is extremely proletarianized these days). The loom worker is proletarian, the capitalist A is turning 4 dollars in wool, 1 dollar in tax, and 2 dollars in labor power for 1 dollar in profit. The sewer is also proletarian, the capitalist B turns 8 dollars in raw materials + 1 dollar tax + 2 dollars labor power into 1 dollar in profit.
Capitalist A and B both make 1 dollar in profit per commodity produced, and so redirect that towards expansion of production with the remainder of their money after covering their necessities. Both proletarians along the supply chain had 1 dollar stolen from them per commodity produced in surplus value, and the "Marxist" at the end is a strawman.
Finally, cost of maintaining the tools used and purchasing new ones I am assuming is a part of the "raw materials" category.
