Very few people have as large of a gap between how smart they are and how smart they think they are. Alan Moore thinks he's really, really, really smart and insightful.

Not even sure why I'm giving this argument the time of day, but to break it down a bit...he's weirdly assuming everyone has super powers in his scenario it seems. If you're the only speedster in the region, you can find a job a whole lot more interesting than pizza deliver. Supply and demand. Personal currier for the richest of the rich comes to mind, if we're just going standard delivery jobs. You'd be able to set your price, too.

And, even if everyone had super powers...well at that point they would be useful too, because the way cities were built and such would adapt to the new super powers. In his speed example, having a car would be impractical. If everyone had superspeed, things would adapt to where, even if it's now comparatively 'normal,' it's still useful.

Hilariously, you could make Moore's same stupid argument for anything. Cars? How are cars useful? What are you going to do...commute to the office?! Deliver goods?! How is that useful? No. Boring can still be useful.

TL;DR: Alan Moore is retarded.