I share your distaste for these payday loan companies, Mikey, and like you I find the names grating, especially "Wonga". Unfortunately i think they are a necessary evil, for as long people need short term loans.
There is always going to be people who are unable to access a bank loan - either because they represent a bad risk, having a poor credit history or previous defaults etc, or because a bank loan simply is not the right kind of loan for them - Many people need a short term loan to bridge the gap,as it were and your standard bank loan does not really fit the bill.
Before these payday loan companies, you had a swathe of people who could be taken advantage of by loan sharks, aware of the desperation of their clients, and imposing ridiculous levels of loan repayments in a completely unregulated fashion, complete with coercive threats of violence for default.
So payday loan companies are at least regulated; at least are very clear about the cost of the loan; are bound by law to negotiate where a customer is in danger of default.
As Woofgang says, the worst fault is their lack of credit checks, and lack of co-operation between the different companies. The stories you here of the worst cases of individuals getting into severe debt through these loans are often people who have taken out more than one loan at a time, from different companies.
The OFT do need to check the market, ensure their is genuine competition and proper regulation of the market to protect the customer from usurious rates and their own worst impulses. But I agree with FF - reporting their loan rates as an APR does not really reflect the true situation.
I cannot think of a decent alternative, except to reiterate the advice I have heard from people like CAB - that folks should make much more use of and be far more aware of Credit Unions......