Payday loans were invented for a special reason: to help tide someone over. Companies are aware of the commercial demands on people these days, not to mention the high cost of living (especially when you are used to a certain lifestyle) and the many emergencies (or opportunities) that can drive someone into a tight spot wherein even credit might not help.
After all, not all landlords accept cards or cheques. Neither does the corner grocery. And especially not cab drivers.
Ho do these loans work?
Basically, you apply for one online. It is usually very easy and you can expect to get the money within day of applying for the loan. But you have to remember that the cash loans online you made ARE payday loans. The companies that loaned you the amount expect to be paid on your pay day, when you get your salary/wages.
If you don't pay up, your loan will gain interest in pretty much the same way (I am just not sure if at also the same rate) you do when you use a credit card. So it is really wise to apply for a payday loan for something really important, and wiser still to pay it as soon as you are able.
Payday loans are not thought up to further get you in debt, or enable people to live well beyond their means some more. It was intituted to help people in a temporary fix, or give a new lease on a purchasing life for people who have bad credit histories they really want to leave in the past.