I think the main difference to “is it upsetting or not” is are you answering a QUESTION or participating in a DISCUSSION?
If a bot asks how to set up a garden or something and you spend a lot of time giving a detailed answer, that would be annoying because it doesn’t care, it isn’t helping, and it’s (possibly) pointless (it could end up helping someone who wasn’t the intended target at a later point, as is often the case with reddit overwhelming google results). Now if the bot is just starting a discussion about something (“What are some gardening techniques you’ve picked up”) where you’re not actually responding to the bot and the original post isn’t really the focus of the topic the posts are, you (hopefully) have a discussion amongst people in the comments, prompted by the bot; the bot is not really important and actually mostly irrelevant.
In the second case it’s not any different from an admin/mod starting some random starter topics just to get the site going. And if it’s relevant to the board I don’t know how many people would really care how the discussion was started even if you hid the bot interaction and it was discovered later.