Eeh, yes and no. I think their ( = Open Source Initiative) main reason for doing so is to give them the right to pursue sites/companies that would use their logo while not actually being open source in some sort of attempt to gain goodwill with the people that would care about it.

You are quite free (http://opensource.org/trademark-guidelines) to use their logo in a lot of cases without the need to contact them at all.

It is not like your average open source advocates are standing on fences wanting the right to put an "endorsed by apple/google/amazon/..." logo on their sites.