Absolutely vile and indefensible, agreed.
I have to say though that the title of the thread is thoroughly dishonest in stating that this is the UKIP position, then making a comparison with the BNP, only then in the body of the post to say that ... err ... actually it was only one of their councillors. And it turns out he was in any case suspended from the party and then lost his seat.
It would be a bit like saying that it is the policy of the Labour Party to defraud people of their pensions so that the senior party members could gamble it away on the gaming tables only then to add that - well, actually it was only one of their former MPs, Robert Maxwell, and he's dead anyway.
With the number of UKIP candidates expanding so much, and bearing in mind that it's not a closed organisation - anyone can join - it would be unsurprising that someone didn't turn up expressing an offensive opinion. Some people just want any old bandwaggon to jump onto.
It's especially unsurprising as Tory HQ has people systematically sifting through all UKIP candidates' social media sites looking for extremist remarks.
I think the real test is how the party then deals with it and they do seem to be making an effort here.
QuintessentialOHara Yes it was indeed a Nazi policy. It was also a very mainstream opinion among "respectable" Fabian and Bloomsbury types. Virginia Woolf thought that mentally disabled children should be put down. Marie Stopes disowned her own son for marrying a woman with short sight, as it would (according to her) contaminate the gene pool. George Bernard Shaw thought that economically unproductive people should be gassed.
In the interwar years eugenics was just as fashionable and respectable a topic at the dinner tables of Highgate and Hampstead as environmentalism is now.
Funnily enough it became much less fashionable after WW2 and there was mass amnesia about what popular opinion had been only a few years previously.