Bots can work (@minnowbooster, @postpromoter and @smartsteem).
But not right now. Currently, you can't get profit from bots because steem token is higher than 3$.

If you pay 5$ to a bot. You get around 10$ upvote (On average).

If bot upvotes you 30 minutes later after the creation of the article, 25% of the rewards goes back to the bot (If it's in the first 30 mins it's 0-25% depending on the time). But bots almost always upvote you later so you lose 25% of the rewards.

Now let's count: 10 x 0.75 = 7.5$
7.5$ is half in SP and half in sbd.
(BTW You don't get 3.75 SP, it's actually 3.75/steem-current-price).
7.5/2 = 3.75 sbd + 3.75 / Steem-Current-Price (Which is about 3.6 now).

Have fun :D