Assuming that the tapes were made/edited by Sahab, it would likely mean that they haven't bothered to standarize their productions and only remember to put the logo in one of the corners out of the way. Professional networks standarize this.
It could at least mean that there are different people doing the editing. Those who tend to put it in the right corner (westernized editing) and those who tend to put it in the left (middle eastern editing).