You make really good points, it's just that if it costs $3 to get to one place and $17 to get to another (in fact if you are going FURTHER from the other direct

You make really good points, it's just that if it costs $3 to get to one place and $17 to get to another (in fact if you are going FURTHER from the other direction, it costs just $4 to the CBD), one has to wonder why there's this enormous cost gradient, and whether that's just a question of consumer price-sensitivity. Theoretically if roads were a problem a rational transport network would incentivise rail use, but in fact taxi use is effectively subsidised by about $10 due to the expense of trains. I'm just talking about Sydney though, don't know about Brisbane.