A bid bot should not have the only purpose of earning steem. It is a way to promote your posts so the risk of a loss is fair.
If you find it worth to use a bot depends on you. There are quite a bunch of them and some of them promise to be profitable and with some you have a chance of a higher ROI but the risk of a loss as well.
To the question in your title, my Magic 8-Ball says:
Hi! I'm a bot, and this answer was posted automatically. Check this post out for more information.
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