Hi and welcome :) I actually have a sentimentality towards Costa coffee, but that's due to my own connections with the place/brand rather than the quality (which could be improved upon, for sure!). Airports are horrible thieves, and as you say, we do tend to fall for them for one reason or another. Me, I like to get up early, even for early as hell flights and have my coffee at home if I can manage it. It's assured quality and a waaay lower price :D So might be worth waking up 30 minutes earlier next time.

By the way, how is/was Tbilisi? I'm reading about a lot of unrest in the news...