Most games with a consistent world and other players on it have a multitude of types of missions/quest.,

though they 're usually meant to give each player more content to keep playing,

some are also an option, is it too difficult/repetitive/just not your thing then the game has plenty of other missions/quests.

Mining/gathering/hunting can work the same,

and it can do that even more so then normal missions/quests, since there is not a pre-set goal that has to be met.

(aka one player goes to hunt lizards and finds he needs to go back to base to heal after two, another kills three)

One thing to remember is that the pay-out has to match the risks,

if a certain undertaking only succeeds in 10% of the cases instead of the usual 90% of the cases,

the pay-out has to be multiplied by 9.

(and if the time/effort needed is different as well ... - you get the picture right?)