Some searching on http://meta.stackoverflow.com came up with the following:

* According to https://meta.stackexchange.com/questions/87890/why-cant-i-suggest-edits-on-se-meta-sites/97371#97371 it's due to the fact that it would add an another burden to moderators which is explained by the following:
> Mostly because the per-site metas are generally low traffic -- some of
> them count daily visits in the *dozens*. 
> 
> That means the moderators will have to do the work, since the 10k site
> users are the only ones that can even see this queue. And on many
> sites, like say Bicycles -- there are exactly zero users at this rep
> level, even after many months.
> 
> [...]
> 
> We were uncomfortable adding Yet Another Queue for Moderators to Look
> At across every site in the network.

- According https://meta.stackexchange.com/questions/78223/per-site-metas-dont-have-ability-of-suggested-edits/78319#78319 (which is older than the above answer) it's a feature that is not needed on meta sites.