I tip in restaurants,10% of the bill even if there is a service charge added, as Tallg said few times earlier hotels staff in Doha never get a service charge, am a hotelier myself and I know it from within. As for grocery, I agree with rami-leb, I prefer to pack my own grocery,but in case it happens and an attendant helped me out I wouldn't mind tipping him 5 riyals, at a gas station, I never tipped in my home country, Lebanon,but looking at those miserable guys working in such an enviroment and high temperatures, I always tip a couple of riyals, plus don't forget gas in Doha is cheaper than water so couple of riyals wouldn't matter.
I tip in restaurants,10% of the bill even if there is a service charge added, as Tallg said few times earlier hotels staff in Doha never get a service charge, am a hotelier myself and I know it from within. As for grocery, I agree with rami-leb, I prefer to pack my own grocery,but in case it happens and an attendant helped me out I wouldn't mind tipping him 5 riyals, at a gas station, I never tipped in my home country, Lebanon,but looking at those miserable guys working in such an enviroment and high temperatures, I always tip a couple of riyals, plus don't forget gas in Doha is cheaper than water so couple of riyals wouldn't matter.