The tabling re: Nabisco worked more to make people aware of the strike than anything else. The boycott is a vehicle for messaging and a call to action that is doable in the context of a relatively unorganized left.

This is generally what boycotts have usually accomplished and what lefties want to see out of them. When they are large enough, they can have a significant material impact on the targets of the boycott, but even then nobody expected a boycott (or mild sanctions or divestment) to end slavery or apartheid. It’s just one tactic that dovetails nicely with overall solidarity, recruiting, getting the word out.

Regardless of the topic, the vast majority of people you will meet will be completely or mostly unaware of any political issue nor who to look to for direction on it. We also don’t control any aspect of the media. Direct calls to action like boycotts create an opportunity to bridge that gap.