How would bad shocks and bad struts effect your tires over a peiod of time?

Well first, they don't effect....they affect your tires causing premature wear. The faster wear happens because the tire is not rolling smoothly over the surface. This causes the tires to get flat spots (sometimes called cupping) and to wear unevenly. It's kind of like your shoes. If you look at the way your shoes wear you can tell where you are putting the most pressure on them. It causes the heal to wear unevenly and sometimes you can wear a hole in the soles long before the shoes are completely worn out. Same thing happens to tires. You will have areas on the tire worn clear down to the threads (belts) and yet some areas still have a lot of rubber left.