Hi Aliflump, I agree with your thoughts. I see the a smoke break and a coffee/chat break as two different things. If you are outside the office having a cigarette you are effectively out of the work place and unable to process your work, but most coffee/chats take place within the workplace and people are still able to process their work.
Also I guess that the smokers will also be taking coffee/tea and chat breaks as well as the smoke breaks, I would be very surprised to hear otherwise.
I agree that smokers who take breaks out of the office should be made to do so in their own time.
I used to work in an office that had flex time. Most smokers would clock off for their smoke break in the allowed flex time which was before 10am, 12 to 2:30 and after 4pm, the vast majority managed to fit their smoke breaks within these times, so it was not really a problem for management.
I now run my own business and we have had to stop staff taking smoke breaks on work time as it is unfair on those who do not smoke. All staff take coffee breaks on work time and of course will stop to have a chat from time to time!