As mentioned in the comments:
Nearly every common data format used by 3D tools can be stored as either ASCII or binary, the difference is only in how the contained data is stored on disk - the actual format does not change. One example for this is the FBX format.
For the second question: It is common practice to use custom formats for 3D models and animations in game engines. The ones used by 3D content creation tools contain a lot of information that is unnecessary for games. Also the data is usually rearranged so that it can be simply read into the corresponding buffers (e.g.: for rendering) at runtime and does not need to be prepared. The conversion from common 3D formats to engine-specific ones is part of the so-called "Asset Conditioning Pipeline" (and is commonly performed either via Plugins, e.g.: for Autodesk Maya, or special standalone tools that are part of the engine)