People are stupid and want things cheap. Nothing matters but the lowest price. At my family's auto parts store, we had to stock 2 brands of many parts so we had a good one and a cheap one to compete with the big chains.
Yes and back when I dealt with this it was only like .75$ or a buck difference. Bearings metal cage or plastic. Plastic would win out most of the time.
And I don't even want to start on the flying public. If they only knew what that cheap airline ticket was actually paying for.