Yeah, also tried this. The biggest thing that prevents me from working in a coffee shop is that it is simply uncomfortable. My home office is totally optimized for my comfort, with a big monitor and a comfy chair. I've tried working from cafes, but if anything they seem to be designed to be a bit uncomfortable to get you to finish your coffee fast.
Yes those are retractable power strips hanging over the tables. Incidentally (re: your username) this place is called Bennu and yes I just wanted to show it off cause it's great, and open 24/7.
Yup, as noted in many other threads that external monitor is critical and the chair, comfortable keyboard and my shelf of reference books are pretty critical, as are ear plugs and headphones.
I floated the idea to a couple coffee shops of buying some Costco 23" monitors and renting them for $4/hour, but nobody bit