I just don't see it as either an exploit or a cheat. I do see it as a whole lot of time spent logging in and logging out.
Going with the example we've been using here, if Bob wants some pirates dead and posts a job notice, and I come along and take that notice, but have not yet killed those pirates, Bob may post another notice.
If I happen to take that notice, but have not yet killed those pirates, Bob may post yet another notice, and I may very well take that notice as well.
And I don't have to log out to do this - I could just as easily sit around in the lounge, watch Bob post notices and keep collecting them. It takes longer, but I don't have to log out to do it.
Once I have all the notices I can handle, I set off and kill some pirates, then return to Bob.
"Bob, you posted you want these guys dead, right? They are." Bob pays up.
"Bob, you posted you want these guys dead, right? They are." Bob pays up.
"Bob, you posted you want these guys dead, right? They are." Bob pays up.
"Bob, you posted you want these guys dead, right? They are." Bob pays up.
"Bob, you posted you want these guys dead, right? They are." Bob pays up.
Since these notices are legal contracts, Bob is obligated to continue to pay up as long as I have contracts.