Clinchers let him carry around a tiny patch kit and some tyre irons, costing 60c, whereas tubulars would require him to carry a whole tyre, and would cost more. Clinchers have now largely caught up, but many cyclists thinking hasn't. This matters more to some people than others - triathletes, mechanical morons and those riding in unsupported races. In this case, you probably deserve what you get. Unfortunately, the riders behind you don't.
Most people still carry a spare tube and do their repairs when they get home.
Tubulars are only repairable most of the time, you virtually never write off a clincher casing due to a puncture. Likewise clincher rims. Some debate over whether tubulars are still lighter and tubular rims stronger. Probably depends on quality you select.