I really really don't understand this. You don't need to level a crafting/gathering class to make enough gil to get by. If you only wish to lvl DoM/DoW you still need to do the same basic thing as crafters and gatherers. You need to take some time to work out which activities will make you most gil. Just as a crafter needs to see what gear the DoM/DoW will want to buy in order to make a profit, you need to see what mats the crafters will want to buy in order to make some gil. Whacking things with a sword can make you very good money. Diremites drop web which crafters need,sheep drop fleece etc.
Don't expect the gil to come your way as a byproduct of playing your DoM/DoW, the DoH/DoL work at making gil and so must you.