Scalping is generally a product of open markets (when demand exceeds available supply) and flaws in the provider's distribution system.
So in most cases when scalping is rampant, it's not unfair to blame the manufacturer for failing to produce enough to meet demand, although this may be due to factors out of their hands. The manufacturer is dependent upon supply channels and OEM providers who may fail to fulfill contracts on time.
So the only real time it's completely acceptable to fault the manufacturer, is in instances of artificially produced scarcity, which is a risk involved strategy to increase demand and ultimately increase sales if the consumer is swayed by such tactics. "Limited Edition" "Inaugural Edition" "First Edition" etc. are sales tactics that fall into this strategy.
So when it comes to scalpers, typically they are providing the service (yes, service) of distributing supply to underserved markets or individuals for a premium or finder's fee.
It's generally only unscrupulous when the scalper attempts to divert a significant portion of local supply in the interest of blocking the manufacturer's distribution plan to increase their reseller's fee.
It should go without saying that manufacturers can kick this practice in the head by simply providing more supply barring hiccups in manufacturing, OEM parts sourcing or even distribution (shipping).







