That is a missing thing since LR Adobe added the map part ... and nobody knows why they just don't add a function to commit this data for a bunch of images or let export use the italic, gray data that reverse encoding found ... they should fix such things instead of completely messing up the import dialog.
You can commit for a single field by clicking on the label left to the field and then select the shown data.
You may want to look at this plugin: http://regex.info/blog/lightroom-goodies/gps
There is an option that lets you export the location suggestions: Catalog Settings > Export Address Suggestions Whenever Address Fields Are Empty.
I agree that the way LR handles address suggestions is pretty bad. The dark font is unreadable on Mac (it's a little better on Windows); if you edit an uncommitted location field, it deletes the auto-filled contents of the other location fields; and there's no way to batch commit all the fields in many pics at once.
Adobe has been silent from day one about its botched design. Please add your vote and opinion on this to this topic in the official Adobe feedback forum: Lightroom: improve control over reverse-geocoded Location metadata. Given that the issue is over three years old, it's less likely Adobe will ever address this, but it's important that they (and other users) have an accurate gauge of what works and what doesn't.
I missed that too.