I must agree that it is frustrating to have a stowaway just pop up on ones ship, and I'm all for marooning on Cutthroat/Padres or forcing them to walk the plank! But there are times when you do want/need more crew members, and if they ask nicely, or one of your current crew invites some one to help out, then that's all well and good.
The problem lies mainly with people's manners, or more specifically, their lack of manners. I think that it's perfectly ok for someone to come aboard and politely ask if they can join your crew. As a matter of fact, I have done it myself; when a friend of mine was sailing with someone I didn't know I teleported to my friend aboard the ship, and then, before I touched anything, I immediatly asked the captain if I could join the party, so to speak. The captain graciously agreed, crewed me, and I sailed with them for the better part of an hour; I got lots of gold, and leveled up my cannon skills to boot. However, had the captain said no, and asked me to leave, I would have thanked them, and left like they had asked
And if a crew member of mine has a friend that they want on board, then they ought to ask before inviting them, it's only polite. However, if I'm short on crew I probably won't say no to another good gunman! But there are times when I would; for instance, I had one person tp to one of my crewmates and try to take my ship from me, when I took it back all he did was whine about wanting to sail. When I foolishly allowed him to take the helm, he immediatly sunk us with a nearly full cargo hold!
I do agree that there ought to be a system in place to get rid of bad stowaways (The plank and the brig are both
phenomonal ideas, and should both be implemented), but at the same time, there are some good stowaways out there, and they should be given the chance to prove themselves worthy to join your crew. Just don't be so quick to judge them all as ****roaches!