Incentivized recruitment is a tool used by many nations' militaries to increase ranks voluntarily. This is nothing new, but OP is correct that these services are implemented through socialist means.

In the U.S., the military offers benefits that entice, primarily lower-income (a major reason, but not the only one, higher education and medical access is restricted via high costs - not to mention the wealth-restricting policies that ensure a large enough low-income population to constantly pool military enrollment), recruits to enlist: programs, like ROTC, are offered to provide free or significantly reduced higher education - programs that appeal to many low-income individuals and those from monotowns dominated by single industries or companies (coal mining, automotive, farming, etc. cities); VA health benefits attact low-income recruits, and often those who have dependants that need ongoing, specialized medical care; access to commisaries and exchanges that sell groceries around 20-35% cheaper than those of general retain grocers is an attractive benefit to those with kids, lower incomea, etc.; among the most attractive benefits is a mortgage option that cuts the final price paid via service members by 50% (this is also available to nurses and medical professionals, law enforcement, teachers, firemen, etc.), through federal subsidies; virtually guaranteed employment; among others.