Mexican citizens reported that they didn't know of such a boycott. And even if they knew, they still would've crossed because they work on the U.S. side. Another person said that products are much cheaper here than they are in Mexico, hence, the necessity to cross the border.
Boycotts take planning. Perhaps having one on a weekend would be more realistic. Weekdays are tough. People need time to plan ahead and make the necessary arrangements, especially when they depend on their jobs.
A protest all along the Texas border is scheduled for the 25th of this month. It would be neat to see what would happen if people stayed home for one day.