I am unsure whether those shoes can be given a new sole down the road. If so, I've had plenty of cheap shoes given new soles for $50 or less over the years, breathing new life into pairs for much less than what AE would charge for the factory service, for example. It's quite possible to get a decade or more of use out of a pair of sub-$100 shoes. People have been doing so for a long, long time. The important thing is to focus on taking care of what you have. You can't prevent a crease from forming, but you can take steps to keep the shoes looking nice. Good shoe trees (search this site) and a good polish and wax are good first steps. Also, heel taps and optionally toe taps, or a rubber bottom attached by a cobbler, can add a good amount of life to a sole: you take care of the upper, these prolong the life of the sole, and the net result are years of service.