The difference being they wouldn't have to sneak like an Afghan would. The type of work eastern europeans tend towards is often cash in hand (labouring and cleaning), so I think they could (and would) find work.
Why didn't the question of the Irish border come up during the referendum? As far as I can tell it's an unanswerable question. You either have border control and ask to see passports, which will fuck the peace process, or you don't, and that means we'll essentially have free movement into the UK.
It would be in bad taste if we were immortal and ridiculing the petty mortal-men for having to deal with death. As it is we all gotta die so it's more making light of a depressing certainty.