[gojomo]

Companies sometimes view their current inventory, pricing, and other details to be their source of proprietary value, and see attempts to copy and offer that information through another outlet as a threat.

This is especially the case if the company wants to be known as the singular best place for their kind of market information, and is the existing leader. (In such a situation, they may see copying their data as an attempt to lbootstrap a competing service, leapfrog them in comprehensiveness/popularity, or apply downward price pressure on the premium pricing their existing dominance allows.) For example, neither Ebay nor Craigslist have looked favorably on their listings being reaggregated anywhere else.

I'd guess Uber would be most likely to object and adopt technical or legal measures to prevent their info being reused in someone else's app. Uber seems most well-known, deep-pocketed, and far-thinking.