You do realize that there are Ad codes available to anyone who creates a website or mobile app? Search Admob or AdSense to get a clearer picture of them. It does not mean the companies advertised are backing Vir2o or StudentConnect; it means they throw some marketing budget into an Ad code company.
The up side is that ECDC probably receives a penny every time someone clicks on an ad (that's the rate using AdMob because I attempted, unsuccessfully, to add it to the app I created). While a penny doesn't sound like much, estimates are that if around 10k-15k users regularly click on ads it will bring in about $200 per month. Problems arise when Vir2o doesn't have nearly that number of users and $200 a month isn't much for a company. Also, the type of ad matters too. Everyone knows Walmart, Ford, Toyota, and other big companies named, so there is essentially no real incentive to click on them; though one that offer coupons or discounts would provide incentive to click on the ad.
Just throwing some thoughts out there.