There are three basic kinds of constraints on a bank's lending activities. First is the regulatory environment and the certainty of enforcement. I don't know much about bank regulation in havens like, say, Antigua, but I think their "regulators" are only concerned with banks that collect deposits from within the country. Leave the locals alone and they will leave you alone.
Second, a bank's lending policies are an extension of the philosophy and professionalism of its management. If a greedy crook buys a bank and staffs it with "pliable" management, bad decisions will be made. A good case study from recent history is the collapse of the Butcher brother's banks in Tennessee. They were lending money to themselves and to each other (each had his own chain of banks), and by the time the examiners caught up with them it was too late. Twenty-nine banks failed.
Third, any bank is constrained in lending by its ability to fund its loans. Funding comes from deposits, and depositors are notoriously skittish about leaving their money in poorly run banks.
So, perhaps we should be adding yet another question to out ever expanding list: Who would the depositors be in an offshore bank run by the PBLS crowd?
OverDraught