The video is disturbing, first the moron taking it ( apparently it was funny till it was someone she knew ), second the pack/mob mentality in full bloom.
Every place is ( "bad" "dangerous") carry what you believe is needed for your survival. I carried a Ruger speed six with 145 gr Silvertips and a folder every day that I lived in chicago during late 1980's. I only "needed" them twice and no shots were fired.
Now I carry my Sigma 40 F, ( yes I have glocks,M&P F & C all in 40 ) but the Sigma has been with me and has not failed. 2 mags, a 638 BUG with 2 reloads, kershaw, light that will never be bright enough or light/small enough, phone, cuffs/ zip tie.
As to the video- you never know when or where someone will lose touch with reality and you find yourself in the middle. Awareness is your best asset, if I see 25 males of mixed race walking towards me, if I am next to my car I will be in it, calling 911, getting out of dodge. They may only want to ask for a ( match, time) I will never know. Bottom line is you need a plan, and a backup plan, and hopefully you can think quickly because you are in an ever changing situation. Better to be aware with a J frame, phone, light then a Glock 18 with drum mag and be oblivious to your surroundings.
If you have to fight to survive, FIGHT TO WIN. Be Safe,