or maybe you didn't log in to steam
I can see the buttons and i'm logged in, but Steam says "Your account does not meet the requirements to use this feature.
Visit Steam Support for more information.", other people are having this problem as well (and they also think of it as voting for some reason, even though that's over now)
I've spent way more than 5 dollars in the Steam store, so i don't know how i'm not meeting their requirement
And i'm certainly NOT limited as i am capable of everything they list as unavailable to limited accounts