Don't let quixotic liberal marketing campaigns lead you into reactionary traps; of course what people decide (or are induced) to send their money on matters to any cohesive material analysis of the circuit of capital, disruptions of the realization phase of the circuit requires boycotts as an available tool, consumption is not merely personal, it's also structural and leveraging that structure requires convincing quite alot of people to INDIVIDUALLY withhold money from a firm

So again, unless you have a magic psychic beacon, the convincing part requires a moral narrative as a component of the necessary organizing. Because the logistics of boycott organizing still requires individual initiative, integrity, and discipline to work

Not purchasing candy is not a component cell of collective action. A component cell of collective action would be showing up to the meetings every week and holding the discipline agreed to within the group based on material analysis of the system you are trying to change

If the component cell of collective action requires showing up to meetings every week to convince people not to purchase candy, then I hate to break it to you, but yes not purchasing candy in that instance does become a component cell of collective action