It is exactly the same in Lucid 10.04, both in Firefox and chromium.
The main google logo can however be downloaded using
I found that url from the page-source info in both browsers, but strangely it is not possible to right click on the image and choose view or copy.
Like you, I don't understand why, and was not even aware of this until a few minutes ago, on reading your post. It does not really matter to me, but nevertheless it would be interesting to know what's going on; perhaps this behaviour is common, but we had simply not noticed it before.