[imauld]

There are other factors besides just volume. I find it easier to concentrate in a cafe than I do in the office and it's not exactly quiet in the average coffee shop. What people are talking about around you also has an impact. The conversations in a cafe for example just seem to blend together and become a sort of white noise.

The discussions in the office however are sometimes related to what I'm working on. So hearing bits and pieces of them stands out in my mind and can get me thinking about that instead. People in cafes are also very unlikely to come up and tap me on the shoulder and start asking questions about completely unrelated topics.

YMMV of course and some people concentrate just fine in loud places. On the other hand the people that say "I don't mind the open office plan, it doesn't bother me" might just be the people who are disrupting everyone else.

[Arizhel]

There's another factor to the coffee shops IMO: who the people are.

In an open-plan office, the people around you are usually your coworkers, the people you see every day and know personally. In a coffee shop, they're usually total strangers, people you might see occasionally at that shop at best, and very likely you'll never see them again.

Also, the strangers at the coffee shop don't care what you're looking at on your laptop, or if you're getting any work done. Coworkers might. Also, strangers at a coffee shop are unlikely to interrupt you; coworkers are very likely to. So at the coffee shop, it's entirely possible to be around other humans without being forced to socialize with them, but not at work.