Before Google was so aggressive about paying everyone to set themselves as the default search engine, Bing used to pay to be the only search option on a number of mobile devices and disable the ability to change that default (presumably because everyone would just switch back to Google). So for a while, a lot of Android devices sold by mobile networks in places like Europe forced searches to Bing with no way to change that.

If the Justice Department contines with this attempt to stop Google paying to be the default, I can easily see this ending in a situation where their non-search competitors are worse off financially and consumers have substantially less choice than they do now.