I think this is a fair critique and it’s something I’ve considered myself. But, I land on the opposite side that you do.
Dream hasn’t created any fields that day “Listen to this x times a day for x days and you will for sure pocket a million dollars” or anything like that. The fields are made to give your being a helpful push in the right direction. How effective that push is will depend on many factors (subconscious limits, personal ability, the situation you were born into, the opportunities available to you, other aspects and energies in your life that affect your earning potential, etc.). From my knowledge Dream and most other makers of fields will tell you that you have to personally be taking action towards your goal.
Dream’s success in marketing his fields is possibly a direct effect of his ability to tap into and utilize wealth generating energies. Also, I think it’s totally possible that someone with a “better” set of circumstances could benefit monetarily from Dream’s wealth/luck fields far more than he himself could due to individual circumstances.
Main point being what I said earlier, these are helpful pushes. Strong pushes in some case, but not instant money making machines. Near limitless other factors come into play. Personally, I’ll take any helpful push I can get.