"Pop" and R&H were both given a fair amount of love at the time. We have the album, we have the singles and we have the videos. For Pop, we even have the fan club release.
R&H was in analog. Plus, the movie did not show an entire concert - just bits of it. The Pop film showed almost an entire show (I know, it was a merge of a few shows - typical for U2).
In other words, I think R&H has a lot more to offer. The trouble is working with Paramount to release some of that footage. If U2 offer to pay for some of the expenses, knowing who will buy this re-release (i.e., hard core fans, where sales are in the hundreds of thousands at best, not millions), I'm sure a deal could be made with Paramount. After all, having some $$ is better than just holding onto the footage with no $$.
And, as many here have said, I'd love some Love Town shows. The Point Depot shows are famous. U2 already released one in mp3 format on iTunes. Why not release it on CD or DVD (if available)?
Therefore, my guess is R&H not only requires the remaster more, but has more to offer. And with the 25 year anniversary in 2013, it seems not a bad time to release it.
If "Pop" is to be re-issued, the 20th anniversary is not until 2017, so there's lots of time for that, if it occurs.