This would make it far easier to build a hotel search engine, which would cause an explosion of competition and innovation in this area. This in turn would undercut the power of the leading agencies, and drive down referral pricing.
But they won't do this. You see the same problem in so many industries. Vendors act like data about their offering is more precious than the offering itself. They make it as hard as possible to build an aggregator, so the aggregation market gets tied up by a tiny handful of players who are willing to invest enough to build a scraping infrastructure. Then they panic that these aggregators have too much gatekeeping power, but rather than encouraging greater competition amongst aggregators, they respond by trying to put the genie back in the bottle.