Coating of antistatic material on the belts or rollers will not help at all, because the charge is still generated (concretely spoken separated). Only by doping the material of which the belts and rollers are made by conducting material like carbon or graphit will cure the problem. Then, the charge separating mechanism is "short-circuited" and charge can no longer be seperated. But such belts and rollers are expensive!

expensive is not always expensive. I have seen many cases where "avoiding the expensive" has cost more than what was avoided.

How are the treadmill users feeling about getting whacked by static
How are the treadmill users feeling about the sudden malfunctions

what if the end result is 2 units sold instead of 2000 units - yes, you have 'saved' the cost a proper belt but you are out of business.

I think that here we have a case I have seen several times before: someone see something and the price tag.
The first reaction is "I can make that for 1/10 the price".
The second reaction should be "there must be a reason it is that expensive, let me find out"
The second reaction often is "I'll build it"

What we are seing here is the difference between design ability and "know-how"

Erik