If airlines are able to have in place a system whereby seating is allocated in advance in order to satisfy the religious sensitivities of a significant number of their passengers that is all well and good. Being a devout atheist my preference would be for a more secular airline. If I flew with Saudi I’d have a good idea of what I’d be letting myself in for. However I think it becomes more of an issue where the airline concerned – as in case of Qatar – is highly reliant on transfer traffic and the passenger profile is highly varied. In this case I think it is unreasonable to expect some passengers to play musical chairs in order to accommodate the wishes of others.