OK chnlong, won't go after you about holding cable, nonetheless, my view of having a Jersey/Guernsey/Gibraltar account is this.
1. The banks sell these like underpowered BMW's, they sell status rather than substance, and often a local solution (UK&HK) is better. Going with the car analogy, why are there so many VW's around?
2. HK is an offshore centre itself, there is no capital gains tax, neither tax on dividends, nor tax on renting your UK house. Why pay more fees?
3. The local offices of offshore want to sell high margin product and that's about that. There is a big game here in selling life insurance wrapped mutual funds and buy to let mortgages. You can get both here with the local and offshore branches.
<EDIT> FORGOT TO MENTION THE REGULATORS IN OFFSHORE ISLAND JURISDICTIONS GIVE YOU VERY LITTLE PROTECTION <END>