I can't shake the nagging sense that the votes sent by these bots are partly for the sake of vanity rather than any real profitability.

Yep. And to be honest, the more you have earnt for a post, the more people might pay attention to it. Bots are pretty controversial. I used to use them when I was a wee whipper steem snapper to boost my steem power so my vote was worth more, but don't anymore.

It's a complicated crazy place, but a fun ride and quite addictive!!

Welcome to Steemit, fellow Aussie. I'll try to upvote you when I see you to give you a little upvote buzz xx