I know plenty of people who have no problem describing themselves as a distinct ethnic identity - Scottish, Polish, Pakistani etc. I think you need to get out more if you hand around with "fish and chips" or "queen", but as I said - South of England. Strange place.
Also, applying Darwinian rules to ethnicity is very dangerous. Holocaust anyone? Or any other genocide for that matter... But, I'm sure that's not what you meant, so I'll say it in another way. Every ethnicity has the right to self determination. I for one still think there is much is Western or even indeed British culture that is worth preserving. I would wager that due to declining birth rates amongst the current majority of this island - future growth is going to be made up of people not native to this island - this is obvious. However a possible problem with this is, will our new growth be sympathetic to our current values and way of life? Whilst Eastern Europeans are not a problem in this respect - other groups certainly are. Especially when they reach a critical mass in terms of population size and start demanding political and social changes; for their benefit only. This is going off topic.. I'll reiterate, there is a distinct culture
to this nation and its only natural that when other distinct cultures enter it, it comes down to a numbers game where one will eventually dominate at the cultural and social expense of others - or they will both be forced together and loose their cultural distinctiveness all together and have only a meaningless consumer capitalist identity to hold them together... Fascist rant over 
Anyway, you are right. I am well off topic and I should spend my day off doing better things... What I really want to say on this topic is - Why are native British potential workers so lazy? I personally blame socialist benefit culture and a feeling of ill disciplined laxity brought on also by modern mass consumer culture. I would like it if these potentially useful class of people would be whipped into shape (literally perhaps - it worked in Wellington's army) and made to work in the jobs that immigrants take, because ultimately taking on immigrants doesn't help those needlessly out of work, it is just a temporary solution to a labour shortage whilst our underclass festers.