I use the phrase "credible application" a lot when I talk about grant submission.
It holds true for manuscript submission as well.
I suspect some people may think that what they perceive as a "dump journal" of last resort will not require the most polished of manuscripts. This isn't true in my experience. Dump journal papers may be limited in scope but it is a mistake to think the journal will take nonsensical crap which has been prepared without much care.
If nothing else, in your snobbery, consider that the reviewers are going to be more likely to think that Acta Bunnica Hoppica Scandinavica Part C is a respectable journal and less likely to think it is a dumping ground. So if you send up something that has been only cursorily prepared, this is going to be an insult to them personally.
This can be the difference between "Major Revisions, resend for review" and "Minor Revisions". This can be the difference between "Reject" and something less final.