Well, I am one of those for a number of reasons. First, I am at the limit of my computer literacy just reading these messages and sending an occasional post myself. I wouldn't know what to do with these programs even if I was able to download them. Second, and most importantly, I am very skeptical as a biologist of mathematicians and physicists trying to claim that their computer simulations have much to say about the biological world.
Biological populations bring in a greater level of complexity and uncertainty beyond the organism.
In my population genetics courses, mathematical models were used only as theoretical approximations of the real world. If you want to know how real populations act, you have to go out and get real observations from real populations. I have no problem understanding that airplanes can be tested completely on computer without the necessity of wind tunnels. The observations are repeateble enough, the calculations precise enough that effective computer simulations are possible. This is just not true of biological populations.