If we can't get some badges (ie, bounties, earning rep, etc) in meta, why are they present here on meta? And if we can't get rid of them, why not make whatever badges we have on main carry over?
All Stack Exchange sites, including meta sites, run off a very similar code base. In fact, the only site that tends to run anything at all different is Meta SO, simply because the developers usually test new code there first, before rolling it out to the other sites.
Because they're running basically the same code, meta sites like this one get the same list of badges. Removing them would potentially mean moving the meta sites to a separate code base, making the changes to remove them, then maintaining two code bases in the future. And even if they went about it in a more maintainable way (config parameters to turn them on and off, for instance), they still would have to put in all the work to do that in the first place. And as it stands, the badges aren't really hurting anything. And there are only a handful such badges, anyway (I think there's something like eight). In fact, the ones for earning rep are still possible; we have thirteen Mortarboards here.
So basically, there's virtually no benefit, and potentially a lot of headache. It's not impossible, but it's very unlikely to ever get done.