From the perspective of the diver certification agencies there is no difference between a sport diver or a recreational diver. But we can make a difference in styles based in how the diver perceives the diving activity. The same difference of styles we can find in other sports and hobbies.
Divers with poor training and bad practices often run out of gas while diving. Well-trained divers have a high awareness of their consumption under water and are always checking the gauge.