Some sports more than other. Football is a joke when it comes to testing. I was a sprinter and played safety on my universities football team. We were D-1 as well. I can't talk about every conference all I know is in the conference I played in. The way the testing went was every so often teams had to produce a certain number of tests. Not the entire team at once. I know for a fact a good percent of the team smoked weed as well as other recreational things. The staff would just use athletes they knew were clean and give others a heads up that if they're on something they need to stop in time for the next test.