Any sort of parasitism is trying to circumvent this process by convincing others that they need software that isn't directly needed for the problem at hand or otherwise forcing people to install software. And that's the type of behavior styled as "questionable" in this discussion. Tactics like omitting a "no thanks", while perfectly legal, seem as questionable in many other contexts.
If you are right, it's not because no good software aught to be promoted and thus this (and by extension of your logic most any type of promotion) can't be legit, but rather that there doesn't exist a non-scummy way of conducting this particular type of promotion. Is that true?
Sure, advertise the crap out of your product, but do it in contexts where people expect to see them. It's like I'd let a friend through my doorstep, and a random salesman tried to sneak in while doors were open.
And first make sure that whatever you're promoting has any value for user. I'm yet to see a single thing install-bundled that is net-positive for user.