Hello!
In most playings of Trader Bob I've seen on PlutoTV, after Johnny O. plugs each SP, the models roll the first SP into place and whichever SP the contestant keeps in each pair, then they pull the blue brand name card to reveal a red Trader Bob card. What was the purpose of that? Was it just for aesthetics or were they expecting the sponsor to pay a second fee when the SP was shown again at the end of the game? In other games when the SPs were always shown a second time, such as Cliff Hangers or Secret X, the blue brand card still appeared. (Of course by the late '90s or so, the blue cards were permanently abandoned in favor of on-screen graphics)
Interestingly, in at least one playing, only the red Trader Bob cards appeared on the podiums and alas, looking through the end credits, I noticed that no SPs that day were sponsored.