It's not strange, just unusual and very new.
Don't you just love how CH4 didn't bother advertising any of their series on ITV?
They didn't bother advertising their BIG 10th Series of any other channels and they only advertised BB11 on sh*tty chavy music channels that they owned.
Then BOOM Channel 5 come along, cool as ****** and just slap an Advert onto ITV1's Ass.
Love them.