I don't think lone immigrants would immigrate if they had to cut contact with people they knew.
It's also a big difference in outlook -- people that would scoff at life extension would also be the people ready to "end" something in life, and not constantly be at the teat of something. For example, young soldiers in WW1. That sort of outlook is alien to most now, modernity's pit of comfort makes a fool of anyone who partakes.
