How are they ripping off consumers? If the price is too high it won't sell, simple as that. People will buy a PSP3000 for £140 instead. It's up to them to set a price they think will work, and UK consumers are historically prepared to pay over the odds. As I speak the PSP Go is appearing on pre-order charts at online stores selling it for £249, even though at Amazon it is £229. UK consumers don't even bother shopping around online, it seems.
UK pricing does not obey any kind of logic. It's typical for RRPs to assume a 1:1 GBP:EUR exchange rate - the DSi was exactly the same as the PSP Go in this respect. It's also typical for UK to have a premium of 20-30% over the US, which is "explained" by VAT being included in the price, even though VAT is currently 15%. But like I said, UK consumers are generally prepared to pay it.