Purchasing lease rights is cheap (relatively), you're right. The return of big $$$ is in royalties via oil & gas or mineral production covered by the leasing of mineral rights.
Not selling lease rights is zero. Repeat zero. It is every mineral rights owner's call whether to accept a lease bid or not. A bid consists of lump sum for the right to drill or dig as the case may be (small return) plus a royalty percentage from sale of the oil & gas, coal, mineral, etc. (big return). I own mineral rights. In one case, a dry hole for oil produced zero royalty thus just a modest payment for the lease, which was not renewed at the end of the lease term. In another case, there was first the small amount of the lease itself, oil was commercially produced and now I have a multi-decade of royalty payments coming in. Gotta love that fracing!
Thanks for the thoughts, and glad to hear that one lease paid off handsomely.
Cool.