Short answer, NO. If you save all the coins and jewlery you find over twenty years you might be able to pay for one knee replacement if you are lucky or have access to a beach in front of a five star hotel. And that's assuming nothing else goes wrong like shoulder, back, hips, wrists, elbows, just about every joint on your body gets stressed. I hurt my leg muscle and it took about two years of pain to recover, just from standing back up after digging.
But gamblers are gamblers. I watched the poker on TV. One pro his family had to take away his credit card. Another lost 22 million is four days and never got it back. At least with MD you don't have to gamble a bunch of money, just your health. Don't buy the crap about getting healthy from detecting. I worked four or five hours every day for a few months and never lost one pound of weight. But it's something to do and you never know what will come up next target.