The question of whether you can skip it is the wrong way to think about it - the real question is when to do it. You actually do need a foundation apron, and the previous answer was right about water and frost, but I'll add this: if you don't do it now, it'll cost way more and be a lot more of a hassle later. The ground is still fresh, construction equipment is nearby - take advantage of that.
Practical tip: make sure the apron slopes away from the house at least 2 - 3 cm per meter of length, otherwise water will pool against the foundation. And dig it deep enough - at least a spade's depth - so it doesn't freeze solid through the winter.