The idea behind it is that everyone engages with the company, not an individual. You visit Sam's widgets, and buy a widget from Sam. A week later, Sam sells the business to Joe and disappears. It's now Joe's widgets, with all the same stuff and people (aside from Sam). Your widget breaks under warranty. Is Joe obligated to fix it?
You can see the obvious problems if you say no. Coincidentally, this is the case with all the AliExpress crap on Amazon.
But if Sam isn't required for business continuity, it can build consumer trust. Even if Sam leaves, customers know they will be taken care of. They can buy with confidence that someone at Sam's Widgets will keep supplying their widget needs.
Yes, it's possible for a corporation to escape liabilities. But it's the case for real people, too. People declare bankruptcy all the time, although there are certain debts that cannot be erased. These often don't apply to corporations.
Have you ever worked at a place and disagreed with a decision made by the higher ups? Imagine if you were on the hook for every single widget you produced, or claim you processed, or whatever else