As said you have to remember these aren't dudes leaving their homes for fun, these are refugees fleeing an oppressive empire. Sure many Xaela tribes probably stick around on the whole 'this is MY home screw those Garleans' style but if someone wants to leave for safer places there are tons of ways for it to happen. When it becomes 'get crushed under this empire's boot and die' vs 'leave, try to hold on to my culture, and return when I can liberate my home' a lot of dudes are gonna take the latter.
We know there are boats taking refugees from their lands, if you knew that when the totally not-nazi empire was breaking your door down it was just a matter of 'get to the coast, find a ship with a friendly captain' to avoid being crushed you're GONNA get there, even if you're in the middle of the desert.
My Xeala is a very traditional tribal type, she super hated that to get to Ul'Dah she had to ride in a hidden hold in a fishing boat with a bunch of filthy other tribes and cowardly Raen, but she did it, because she'd be fine to swallow her pride and take a bath later to get the stink of other tribe off her if it means having a chance in a safer land.
We know there are boats taking refugees from their lands, if you knew that when the totally not-nazi empire was breaking your door down it was just a matter of 'get to the coast, find a ship with a friendly captain' to avoid being crushed you're GONNA get there, even if you're in the middle of the desert.
My Xeala is a very traditional tribal type, she super hated that to get to Ul'Dah she had to ride in a hidden hold in a fishing boat with a bunch of filthy other tribes and cowardly Raen, but she did it, because she'd be fine to swallow her pride and take a bath later to get the stink of other tribe off her if it means having a chance in a safer land.