Agree with Thomo to a degree. Obvioulsy rule "e'' and the "transition" stuff was put in there to prevent a situation where someone might try catching waves on their knees and stomach, standing up with the paddle and ripping on a tiny board, thus these rules were put there I'd say to keep it true to what is SUP.
And in a prefect world yes, all comps would be held on a nice clean point break or perfect A frame peak, so paddling out whilst standing and staying standing the entire heat is not an issue. However on a regular beachbreak, that may well be closing out, how one gets out shouldn't really be taken into account when they're up and riding a wave.
But realistically most judges have enough trouble spotting all the surfers all at once when they're riding waves, let alone worrying what they're doing as they paddle back out again