Ugh... the level of ignorance in this thread is frightening. RavenNev stated it well.
Gil generated (from quests, npc's, vendoring, dungeons etc.) is not the same thing as gil earned from the market wards. The problem here is that the value's for gil generated seem to be far lower than the amount taken out by the system.

At level 50 repairs run 2-5k as people have stated. Teleport to a location outside your region? that's 4-500 gil. Teleporting in region while doing storyline/quests/farming/whatever? Those short hops add up too. Right now I'm easily spending 5-10k a day in dungeons and teleporting alone. Yeah I earn plenty of gil through the wards via botany and carpentry... but eventually my customers who are all spending 5-10k a day (not too mention the 5% the ah is deleting from the economy) or more will run out of money too.

Dungeons are a net loss on gil at level 50.
Leve's provide negligible amounts of gil and have daily limits on allowances.
Quests are not a renewable resource and have no place in this discussion.
We can only hope that SE is planning to address this.