Who decided indenting with spaces was a good idea?

I have had various discussions over the years with developers about coding standards and consistency. At the start of a new project a team will/should sit down and hash out a common coding style guideline to follow. I’ve always believed that the consistency of the codebase is more important than my own personal coding preferences, so I never complained much when a decision doesn’t go the way I’d like.
One decision that I’ve seen many times and have never understood is the use of spaces instead of tabs to indent code. To me it seems that this is something that people have just gotten used to seeing and have very few actual reasons for preferring it. Similar to how many people pronounce words incorrectly and resist correction because the correct way “sounds weird.” So instead of making the same mistake, I’ve decided to list the reasons for using tabs instead of spaces for indentation of code.
- tabs are a single character that represents indentation, this makes it the “correct” choice for indentation of code.
- when code is indented with tabs, the indentation amount (2 spaces, 4, 8) becomes a developer preference that can be set in the developer’s IDE.
- tabs actually use less space on disk as only one character is stored instead of 2, 4 or 8.
- indentation mistakes are harder to make and easier to see (like 3 spaces instead of 4)
- spaces look funny (OK, that one was a joke)
It seems to me that indenting with spaces is akin to making a new paragraph in html via 2 <br> tabs. Yes it achieves the same visual result, but the <p> tag has a purpose, why would you NOT use it?