>>2370527Weworks are really good for a bit of free food and drink (booze). Do a little research beforehand and check which companies have an office there and say you have a meeting. The guard will ask you to sign in and let you through to the common area where you can feed yourself. Just a make sure you obscure your face in the check in photo so that the host you’re a “guest” of doesn’t find you.
If the receptionist doesn’t let you in, say that’s you’re already really late and are probably gonna get sacked if you miss this meeting
The very large ones like Poultry and Devonshire place are really good for this.
Again for London you can also join
meet-up.com and look out for tech meet-ups eg: react, JavaScript, typescript at Facebook or google or some place in Moorgate as they always have free pizza and beer