The first thing that you said is the true purpose of the bots, and the rest are just an addition. But whether using a bot or not, a trader can still expect more, especially if he thinks the strategy that he uses are really good. If he doesn't have his own strategy because he still lacks of knowledge and skills, he can use someone's pre-configured bot and he can expect the same thing, especially if the bot owners promised them that their bots are highly profitable.

Rather, you can say the owners of those bots won't ever publicize it but they can just solo the gains that they can get out of that bot because if all will use it, who will lose on a trade and give us a profit?