I dont think there is anything to do in check in is there?? All bars,shops and other things are through security arent they??
I don't know Manchester airport that well - have been through it twice (
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- too big for me and they were really slow checking us in) But there's definitely places to eat and drink this side. (We were so slow to be checked in that we had to go straight on the plane so missed everything through security).
When you get there go straight to your check in desk and get rid of your bags. Then stay this side so you can pop out for a ciggie but keep your eye on the TV monitors and go straight to gate when requested as you may have a long walk to get to it.
Also keep an eye on the security queue as when we were at Manchester airport not only were they slow checking us in but the queue for security clearance was across the airport and to the front door
I've just come back from Gerona airport in Costa Brava Spain and we could smoke once through check in at the outside tables (took drink with us etc).