Will the economic boycott have any positive effect?

What is the point of a single day economic boycott?

Not shopping at these places may have an effect on a single day of sales, but people are stocking up before and replenishing after. Couldn’t these retailers just raise prices on Saturday staging a higher demand?

Some stores are already using dynamic pricing, so what’s to stop them from pumping weekend prices higher?

If we really want to “make them feel it” shouldn’t we boycott those stores altogether?