And if that table is regenerated every hour by some algorithm ?

I agree that Google can fix this. But don't assume it's a quick 5 minute fix with an SQL client.

It's just odd that they're willing to pay money instead of doing the tiny change.

They probably don't want to set a precedent of doing this. For example, if BMW wants youtube.com/beemer, but frank beemer has had it for years, they probably don't want a precedent where poor Frankie gets to keep it.

Lush pays for their YouTube features and for ads, Matthew Lush does not.

Agreed, unless they got a significant amount of money to change the URL in the first place...in which case paying for marketing materials would most likely be a drop in the bucket.