Why wasn’t the INS there to gather them all and take them to the border?
The border in AZ is very large, rough, easily hid in and usually wadeable. If you’ve never seen it, that would be a trip worth your time (take plenty of water!). The Texas one is much the same with several crossings for the small communities to cross back and forth; very small areas of swimming - some in the Big Bend Park in the canyons. It’s hard to spot someone on foot - especially if dressed in the same colorings..