That assumes that bob shares his improvements for free. i have seen several optimized miners people have attempted(some sucessfully) to sell. Bitcoin is a very open market everyone has an equal opourtunity to earn bitcoins that does not mean that everyone earns an equal number of bitcoins.
True. I just feel like everything in the bitcoin world should be 'free' free bitcoin transactions, free products and services. But I guess there is not really way of going around it, the appropriate people need to be awarded one way or another.