Let's just compare mining and hunting: I have two alts, one is at level 10 in mining and basically get an ore each time he tries (I know the so called 'hot spots', though. And they sure are real!). The other is a hunter; he knows how to use a club, wear armor plates and protect himself with a shield, and that's it. Also he can repair his equipment.
I think the time it took to raise mining at ten is quite equivalent to the time it takes to raise a weapon skill up to, let's say, between 35 and 50.
So mining an ore takes five seconds, considering you dig one out the most often, let's say in ten minutes you can dig 75 ores (you have to move, rest some time and such) with a bit of luck.
A weapon skill of 40 let you kill tlokes fairly easily. You got an average of one tloke bit out of three kills, I believe. Let's say it takes 10 seconds to kill one. You got like 30 loots in ten minutes.
Depending on what you dig, mining makes more money (some people pay 300 Trias for a tin ore!), not even smelting your ores! Plus when you hunt you have to repair your equipment, and you have to stop to heal (then you loose time or money, depending on the fact you use healing device or not).
So yeah, hunting does make less money than other trades (not including cooking (by the way, why is a healing potion more expensive than Q200 food??) of course).