This is the closest it gets to calling out the the 30% but I agree, it should be clearer.
[0] https://github.com/floatinghotpot/cordova-admob-pro/wiki/Lic...
Ehh, I disagree. We all know developers would click through any terms without reading anyway and the onerous is on us to read the license before we integrate 3rd party code, which we rarely do. I see this as /just deserts/, a sort of hat tip and "well played sir". The 30% that is not mentioned is the sticking point, the 2% is absolutely reasonable and I might even say I'd think 30% is reasonable IF it had been called out in the license.
https://github.com/floatinghotpot/cordova-admob-pro/blob/mas...
It's free software provided without warranty. It's right there in the MIT license.