Why are payday loan interest rates so high?

Fees and interest rates are high for payday loans, but in the long term may not be a problem. Payday loans and cash advances only run on the waiting time until the next payday. This is usually about a week maybe a month if paid monthly only. APR rates are high too, from 456% to over 2000% in some cases. Most loans are $ 100 to $ 1500. Percent rates that are usually $ 15 to $ 25. If they are older, can be a special service, just to get a loan faster than normal time.