I just don't understand why you would want to mine on a machine that delivers significantly worse results
For most people, it's all the have and they just want to test out mining to see if they should spend more on a dedicated miner.
Maybe, but they will get demotivated pretty fast, because on macs it is nearly impossible to turn a profit after electricity.
Of course they will make no profit, but they get to sign up for a pool, figure out how pools work, and figure out how hash rate and other mining things work. The also will make a fraction of a coin, so they can also use that to test out the crypto coin network. I used to mine on a mac as soon as I discovered this whole mining thing