Once you have shared that knowledge, or provide an offer such as a consultation at no cost, it is out there and one must accept that fact. Once shared, one cannot complain that it is being used by someone else. You can hope they cite you, but unless it is trademarked or copywritten, anyone can do with it what they please.
I have taught and provided others with tools and knowledge and they, in turn, have taken those tools and knowledge and have taught others. I am perfectly okay with that. The people they teach may have a rudimentary idea of how it works and may use it, but they will not get the results that they want because they did not learn it from the source. This is akin to the game where you whisper something to someone in a circle and they do the same to the next person and by the time it gets to the end, it is very rare that it is the same as it was originally.
Oscar Wilde stated that: “Imitation is the sincerest form of flattery that mediocrity can pay to greatness.” Think about that the next time someone uses your content.
One can, however, go from greatness to mediocrity if you offer something like a consultation and then renege on that offer. There may be a time where you may feel that you no longer want to make this available and that is perfectly fine. The issue though is the perception that you are now portraying. You can certainly have a cutoff date, but all of those that have scheduled a consultation, or, taken you up on any other offer you must follow through on it. By not doing so, you are saying loud and clear: “My word cannot be trusted.” Is that something that you really want?
Those that work with me, do so because they see the value, thinking, and ideology that I have and it meets with theirs. They get that only by me providing them with the information to make that decision.
In business as in life, simply do what you said you were going to do. It’s called integrity which without it, any form of success will never materialize.