Maybe worth noting that there is a subtle difference between different types of what should more correctly be called "instructed caving".
There is pressure for young people, as part of their normal education, to be given experience of different outdoor pursuits, one of which is caving. This is most often done through local authority centres or else by local authorities buying in expertise from a caver who has taken the trouble to take some qualification relating to safety issues, conservation, etc.
This is not quite in the same ball park as a freelance cave instructor who makes money by advertising his/her services to take non-cavers underground and is thus effectively making money from using someone else's land. Though many freelance cavers do some work for local authorities, schools, etc.
Worth noting also that some landowners make a charge for instructed groups (or, indeed, ordinary cavers) to go down caves on their - usually calling it a Trespass fee. I, personally, don't have a problem with that.
Also worth noting that some "landowners" are actually business syndicates, sometimes not even British, who make money from the government subsidy for not doing anything with their land except keep it as moorland. They are in totally different class from small landowners or tenant farmers.