You can also buy pharmaceuticals at Walmart. What is your argument?

That's a powered scooter, not an electric wheelchair. They may look the same to a layperson, but they're not - one is highly regulated and has a lot of people making a lot of money off them, the other is a scooter.

Some of these wheelchairs are 75k. They're custom made to your body size for maximum comfort and the features are customized to your disability.

These aren't off the shelf mobility products. Each one is assembled to specification.

As the sibling comments noted, we're talking about bespoke wheelchairs for people with severe mobility disability (MS, ALS, etc). Things like Stephen Hawking's chair.