The reason is simple but absolutely wasn't that: they both subsidized their customers' rides to the tune of a billion dollars in a bid to undercut one another.
As it turns out taxi riders care a lot more about price than they do about the company's cultural sensitivities.
This isn't unusual in the transportation sector. In the 80s UK bus companies would undercut each other in a bid to achieve a monopoly. Some even offered completely free buses in a bid to drive their competitors out of business.