Japan engineers build a transformer car that turns into a robot - but with people inside it. It can drive, and also walk - but at only 100 meters per hour. Video. Not very practical, but it is a proof of concept.
And exactly what concept would that be, Reelya? To what possible use do you foresee transforming automobiles being put?
Proof of concept that it can be done, even if just for the fun of it? I also notice that they left the support straps on, so, it must not be very stable, or maybe that's just standard safety procedure.
Yup, the article points out possible uses, e.g. tourism, promotion and parades. Sure you can call those things "pointless", but a vast chunk of humanity's resources get spent on pointless for-fun things.
If someone builds
one working "transformer" then other people will want to make better ones, which is why proof of concept models are important. They spur further development.
Also, in a future where bipedal robots have uses, but where we still have roads, you're going to need to move the robots around to different locations, and having them jog down the roads isn't a good solution. e.g. you're going to need specialized trucks and skilled staff to handle them. A bipedal robot that converts to a road-legal wheeled form
might be more cost-effective in some use cases than the combination of bipedal robots and trucks. Similar to how a pure boat is better on water and a pure truck is better on land, but we
still make amphibious vehicles which can work on both.