Tis makes sense, for a lot of reasons.
TJ’s Airport terminal is literally right on the border.
Parking your car in the US, and walking across saves the hassle of the almost always crowded border crossings, possibly saving hours.
For a bunch of reasons (fuel,TSA,taxes etc.), flying out of TJ can be MUCH cheaper than flying out of SD or LAX to a bunch of Latin/South American destinations.
Good. Since everything is so cheap and wonderful there, maybe lots of the parasite population will move home.
The rest of us are tired of paying for all the freebies they get from us.
Be nice if we could charge them for that as they walk South to try and have their cake and eat it too.