@MSO/Tom, I travel only in Europe, mostly to the northern part; Norway, Denmark, Sweden, Finland and sometimes to Germany, Austria, Slovakia, Czechia, Slovenia, Italy. I could buy pipe tobacco at every airport I have been travelling through so far. This Summer I will go to Hungary and I have already checked Budapest airport's tobacco offers and MacBaren Scottish mixture, Danish Black Vanilla, W.Ø. Larsen, Danske Club black and Orlik (up to 250g) are available there as well - Orlik is the most interesting for me, I don't really like the others, but at least they have a selection of pipe tobacco. In Austria and Germany you can find the same products at the airports.
Here, in Iceland we have tax-free shop in both directions, so doesn't matter if I arrive or leave home, I can buy tax-free tobacco here as well. It sounds great, but here we have only Special Dublin, Skandinavik and Half & Half... So I always buy tobacco abroad and booze here, nothing can beat Icelandic beer. :D