It's interesting how organizations put their own spin on events to make them seem more dramatic. First, a little information on pepper guns. They are a low velocity weapon (and I use the term loosely) with an effective range of about 30 feet. Any further than that and the pepperball may not break. At a range of three feet, the ball will cause bruising and welts but will not break the skin or cause any internal injuries. All agents authorized to use this weapon must first be shot with it themselves at close range.
The lights set up at the camp put out a lot of heat. When the cardboard was placed against the light, there was a risk of catching it on fire. Some agents overreacted, not knowing the reason why there was a commotion. Once the cardboard was about five feet away from the light, it was allowed to remain.
As far as the continental breakfast, it is illegal to pass ANYTHING across the border except at a designated port of entry. The border patrol is tasked with enforcing that law. Noborders may disagree with the law, but it is still the law. The border patrol is allowing noborders to violate several laws so they can have their demonstration. In exchange, there is an increased presence of agents to ensure that the laws can still be enforced. You may have noticed that even though government property was vandalized, nobody was arrested.
The area where the camp is set up is one of the more dangerous areas around Calexico. Many smugglers head to that area when being pursued. The road is closed to regular traffic during the demonstration to protect participants from some of the dangers posed by the smuggling organizations. In addition, many drivers do not slow down sufficiently for the corner and some end up driving into the area where the camp is set up or even into the canal.
The border patrol believes that some protesters may instigate violence, as happened the other day when the vehicle was damaged, and a show of force is believed to be necessary to keep the demonstration peaceful. Peace and force are not two terms that go well together, but sometimes necessary.
As for the demonstration itself, there is nobody in Calexico with the power to make any changes to immigration law. The demonstration is basically pointless and without effect. Once the demonstration is over, life will return to normal and within a week, very few people will even have cause to remember the event ever happened.
Enjoy the time you are spending together singing and dancing, but don't think that you have accomplished anything. Even violence and destruction will only serve to make the laws more restrictive, both for immigration and for how demonstrations are allowed to take place.