I very rarely get smiles at Heathrow airport or any other airport in the west for that matter. If I smile first, sometimes they scowl and sometimes they smile back. Some are amazingly friendly and some are just plain cold. Could it be that expats here have already made up their minds about Qataris and use any negative incident as confirmation that this place is unwelcoming? I have met my share of unwelcoming people in the west. I consider them unwelcoming people with issues, no more, no less. Also, bear in mind that Qataris are quite reserved and tend to wear poker faces. Its a cultural thing.