How is this possible?

So, I've seen this message a couple of times on Wikipedia:

And the first question I have is, "Dear Wikipedia, you do understand what a primary source is, don't you?" Because I just don't understand how you could have too many primary sources.

Now, there was a second part to this message which said "Please improve this by adding secondary or tertiary sources". I find this even more interesting, given that Wikipedia has this to say of tertiary sources: "Some tertiary sources are not to be used for academic research, unless they can also be used as secondary sources, or to find other sources." So, a tertiary source isn't even completely accepted as a source in academia, and shouldn't an encyclopedia meet academic standards (ha ha--aren't I a dreamer)?

Granted, I'm an archivist and I spend my work week with primary sources. But still. This just isn't right.