What is the ruling on taking payment in exchange for enabling others to use a scanner to search for gold in the earth, regardless of whether gold is found or not, and is this considered consuming people's wealth unlawfully?

There is no harm in renting out machinery used for discovering minerals underground, nor in renting it for that purpose for a known period at a known fee. This holds true whether the renter achieves their goal or not, or even if they do not use the machinery until the rental period expires, provided there was no impediment to their utilization of it. In these cases, the agreed-upon rent is established.