I don't really care if people use tabs or spaces as long as the codebase is consistent, but aligning things in the middle of a line is my pet peeve. It's fiddly to maintain, it ruins source control because it requires you to edit many lines when you change one, and worst of all, it makes it impossible to use a proportional typeface.
I also use spaces for mid-line alignment and tabs exclusively for identation. I think this is called "smart tabs"?