Safeway Bonus Points - 100 Certificate

Does anybody know how you receive the 100 Bonus Point Certificates from Safeway?

From what I gather and have heard from moms who have turned in these bonus points is that they believe they received these Bonus Points because they bought a certain number of Campbell's and Pepperidge Products. This certificate automatically printed out of a Catalina machine which sits next to the till when checking out.

I was unaware of this promotion but would like to know if Safeway advertises these promotions in their weekly flyer, or if Campbell's advertises these promotions on their web site?

I was wondering if I should contact the local Campbell's Sales Rep directly to see when a similar promotion would be running again at Safeway or any other retailer. I know our school would be able to accumulate a lot of points with this promotion. It seems like a no brainer. I am just looking for details.

Thanks!