Yeah, but searching for the actual word is much easier than searching the acronym. Take MAC for example (tried out with german google, so your experience may vary).

I get a cosmetics site, apple.com and store.apple.com, wikipedia article about the mac adress and a clothing site. Message Authentication Code is nowhere to be found.

Yes, I took one of the harder ones, AES is on the first position, but still it is nice to know the words behind an acronym.