That's because TSA doesn't do the security at SFO [1] SF has had issues with drug trafficking through the airport due to this [2]. [1]: https://www.sfgate.com/

That's because TSA doesn't do the security at SFO [1] SF has had issues with drug trafficking through the airport due to this [2]. [1]: https://www.sfgate.com/travel/article/answering-holiday-travel-tsa-questions-17595879.php https://www.sfgate.com/travel/article/answering-holiday-trav... [2]: https://www.sfgate.com/cannabis/article/sfo-armed-robbery-uncovered-drug-smuggling-ring-18161928.php https://www.sfgate.com/cannabis/article/sfo-armed-robbery-un...