Hello Dwight,
As already mentioned, all that is supporting your car on the road is the four contact patches that are the size of your palm, IMHO, you could be putting your car (and yourself) on harms way, specially on a wet road. I noticed that when the rear tires are worn the end is no longer stable..
However, many of us are
on a day to day struggle to meet ends, and having four cars on the house does not help much, and as you know tires are not cheap..
A few years ago I needed tires (with no cash flow..) and the local 'Just Tires' offered a Good Year credit card that offers 6 months No interest, so as long as you pay the balance within six months you are free to go.
Needless to say, my tire bill never ends because as as soon as I end paying tires on one car there is always another one on the queue..
Good luck!