(BTW Switzerland also had a referendum where they decided to no longer take migrants in 2014)
If you get paid €10 an hour and your neighbor makes £10 an hour. Who makes more money (and always has for the past 40 years)?
Maybe that analogy will help.
Yeah, see my reply to your sibling comment. I was so distracted by the "same" that I didn't think about how prices of goods in other countries are often so high that the numbers do get close (i.e. a $100 widget will just happen to cost about £100 or 100€).
Regarding the pound thing. Money does not work like that.
For example 1 ¥ (Japanese Yen) is worth £ 0.0071. Is the Yen worthless?
Money does work like that when you are talking about an actual comparable wage. The pound and euro are much more comparable because you could get the same job for the same number, just in a currency that is worth more so you can send some back to your home country.(like many Immigrants do in many host countries)
Switzerland is also a continental country, you can literally walk to it if you were so inclined from any of the EU nations (except the UK and Republic of Ireland) and not spend a penny to get there.
It is mainly common sense vs what people feel is right, really.