Realistically speaking how often is that going to apply in practical terms?
Chances are that if you won't use your sneak attack on your first attack in the turn, you simply won't have any more chances to use it period, because "saving it for later" will mean being out of stealth.
Not to mention that at low levels more often than not your "first attack" is your ONLY attack.
If the requement for sneak attack would be only stealth, you would be right, but your second attack can be aimed at someone who was hit with Guiding bolt in previous round for example. So a rogue with 2 weapons or under haste effect can find some real use for that control over sneak attack. And then it's quite irrelevent how is it on low leveles, we will go above them eventually.
