First off, your problem may be the advice animal "route." It's not very creative or novel. They're sorta played out for most people at the hipster core of Web Culture.
Second (this coming from someone who isn't as savvy as other moderators,) I think it's a matter of it being "forced." It takes away from the "pure" nature of memes as most users here see them.
Many (if not a massive majority of) memes aren't "bootstrapped" or "astroturfed" (the two mean the same thing with differences in connotation and context.) Usually, something is used used once somewhere (origin), many people think it's funny or appropriate for their own uses (spread), and people begin to use it in different ways and in different contexts (deviations, mutations, etc.) That isn't to say that a meme isn't a meme if it is astroturfed:
via Chris Menning:
Astroturfing occurs when a viral video or other phenomenon is staged or faked by an organization or other group of connnected individuals looking to promote a product, yet hide the fact that they are advertising. Knowing the difference between a grassroots movement and an astroturf movement is essential when considering a meme’s legitimacy.
…but it does take away from the spontaneity of the meme. When people see what you're trying to do, then they'll often actively work against it. The Internet does not seem to like to be, shall we say, "experimented" on in such a way. Trolling is generally targeted. A meme (I believe by its definition in Web Culture) needs to be used in various ways and in various contexts, meaning that the "target" is the Internet on the whole, and "seeing what other people might do with them" may imply that you're experimenting or doing experimental science on the Internet. There is observation. And "lurking" and documenting is fine (heck, that's what we do here, and some people still don't like that,) but you're consciously introducing an factor that wasn't present before to induce behavior. It doesn't "smell" right, I guess.
When you specifically desire to propagate an advice animal or any sort of potential Web phenomenon and you take action, it is immediately "forced." "Bootstrapping" implies forcing a meme, so there is no difference in practicality between "bootstrapping" and "astroturfing." There might be an implication that astroturfing is done by a group, but you, yourself, are an implementing entity, at the least. So it's still close enough to astroturfing.
When you're on the Internet, you can't apply pressure to anyone to do anything. Implying that pressure immediately gets you backlash. It seems like you're aware of that fact that you can't make anyone do anything on the Internet. But that also means that (even with your efforts,) people don't have to think the advice animals are funny, and they don't have to use them.
That seems to be the case here.
If people want to use it, forced or not, then they will. You can use your own "catchphrase" or something and it might not be seen as you trying to get other people to use it, but using a unique advice animal (it's funneh cuz advice animals are generally the same lulz oxymorons r cool) repeatedly will immediately come off as you trying to force a meme into use.
But enough psychobabble as to why it's poor form.
You might want to look at the other supposed origins of advice animals and see how they came about. If you can "manipulate the Internet" properly, then you may be able to take cues from those newer advice animals and astroturf from there. See what kinds of advice animals took off in what contexts and determine what sites are most likely to use a certain advice animal.
But at the end of the day, it requires acceptance and use from other people for it to get going. If you don't have that (regardless of how clever or funny you think it is and very well may be,) then you won't have any spread.
Do you have any other questions? Or is anything unclear from this answer? amanda thinks there isn't a difference, and I think I've said the same thing. I just posit that the lack of difference is why it's poor form.
