Not necessarily. A lot of poor people have no credit. They may pay their bills on time, but lack credit cards or bank accounts.
And the banks aren't exactly welcoming to people with no credit. You don't even have to be poor. When I needed a loan to buy a car - not a new car, but a used car from a guy where I worked - no bank would give me the money. I was working as a cook, had been at the same job for awhile, but didn't have any credit history. No bad credit, no bankruptcies, just no credit, so they wouldn't cough up a dime. I managed to get a loan from a credit union eventually, but the rate was pretty high.
A few years later I moved to a new town and tried to open an account at the bank down the street. Since I had just the one loan on my credit history and not much else, the only account they would open was one with a minimum balance bigger than my meager paycheck. Again, not poor, just not making a lot of money and no credit.
So I wound up using a check cashing place when I got paid. They took a percentage of my little paycheck and charged for the money orders I bought to pay my bills. If I'd had any kind of emergency like a medical problem or a car wreck I'd have been screwed. It took awhile to get on my feet, but I did. That was over 20 years ago, and it is worse now. Want to rent an apartment? Credit check. Open a bank account? Credit check. Employers are running credit checks now, too, so you may not even be able to get a job to put money in the bank that won't take your business.
So financially you can hit rock bottom without ever leaving the ground...and that's where the vultures from the payday loan industry circle.