There is the principal difference, which is well seen in how software engineers compare to all other sorts of engineers (less so today, as apparently all engineers now are a little software engineers).

Plumbers, welders and civil engineers are supposedly trained in their area and know well how to solve a pretty well defined set of problems. Much better defined than a similar set for software engineers. So for plumbers "execution" is paramount, not - mostly not - the creative side of designing. While software is bigger, more vague and with less clear-cut recipes area.

This is less and less true lately - last couple of decades in particular - as more and more software engineers are actual plumbers in this sense. Those don't make drainage systems - or, write program - in their spare time - they take photos, sing or enjoy woodworking. Even though their employers seek people who'd program in spare time.

Those who do - there are plenty of those who enjoy programming more than just to make it a profession - can be attributed to first or second group. I think the third group actually has plenty of them as well. They don't need to think of technology to be all, end all of one's existence - they just enjoy programming, and doing little, or pretty big (this is harder, so has a lesser chance) work pieces for people. But they don't necessarily not programming on weekends.