"Where do you draw the line?" is almost always a trivial rephrasing of the slippery slope fallacy. We live in a world where there are no lines, and we draw them in arbitrary places so that we can make the world work. If that bothers you, you are just going to have to adjust your worldview to be compatible with the reality you were born into.

Help me understand how your comment doesn't imply that all ethics are situational and relative?

As far as I can see, the two concepts have no bearing on each other whatsoever, but in any case, I can't help you to understand how something doesn't imply something else. You're going to have to justify how it does imply that. You can start by defining "situational" and "relative".

I agree with others that this sounds a bit like a slippery slope fallacy. However, thought of a bit differently, that practicing on the smaller things helps you on the larger, makes more sense to me.

That said, I'm not sure if there's data to support that. Does being meticulous in your speech and not telling white lies make you less likely to cheat on your wife, say?

I draw the line at something big.

Firstly, morals differ a little, as illustrated by the discussion around. Secondly, appreciating craftsmanship does not necessarily imply approving of purpose.