Moreau was at one point, Bernadotte seemingly as well, due to their treatment by their master they became desillusioned and being men of honour they did not just endure injustice.
As for Dupont, I have to find out more and read Titeux front to cover and as well.
Also I must read Maag, Dr. Albert : Geschichte der Schweizertruppen im Kriege Napoleons I - in Spanien und Portugal (1807 - 1814), 1. Band, Biel 1892 - which as a good section about Dupont in Spain and Baylen.