Why would anyone object to someone having a few stickers on their boat? If you can find a sponsor to keep the costs down a little then IMHO that's awesome.
It doesn't necessarily say anything about how professional they are though.

As for the Pro's, the ones I have met so far are very helpful and are responsible for taking the sport as a whole to another level.

Edit: The only case that I know of where some yacht had to remove his stickers was in Belgium (where else? <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />), they where promoting a political campaign.