Tobold the tauren shaman is up to level 10, and now has 64 gold. That involved fishing at level 7 in a level 72 zone, Dragonblight. Few people realize that outside instances you can reach any point in the game with any level of character, if you don't mind dying a lot. So now, back from my trip to Northrend, I'm again in a zone not adequate for my level, fishing in Cragpool Lake in Stonetalon Mountains to find the Weather-Beaten Journal needed to find fish pools from your mini-map. I'll need that for my planned excursion to Stranglethorn vale to participate in the fishing contest there with my low-level character.
All this obviously isn't leveling me up very fast. Gaining power for you character, in the form of levels and gear, is one of the prime motivators for playing MMORPGs. Thus people tend to choose the most efficient path to gain power. But consider this for a minute: By definition there is only one most efficient path. The further you stray from the path of optimum efficiency, the more options you have. And ultimately, especially if you are on your Xth alt, doing something very different can be more fun than doing something very efficient.