I don't think it's possible to measure and avoid the "as long as it is not done by getting money with the free work of others". To get our tools for free is a result of the very nature of the computer and the Internet (copying costs practically nothing).

I think it's absolutely moral to write commercial software by using Emacs. All the people who have collaborated (at least enough to have any impact) have gained commercial rewards for it. For example their work on Emacs has improved their skills, was used on a CV to find work etc. By only using it (making it more popular) I contribute to their commercial success (if they at all try to achieve it). By having donated to the FSF, I contribute even more. Heck, even by having donated to Wikipedia I may have contributed to their commercial success. So no, I absolutely don't have any moral problems with using emacs to write commercial software.