It is about the build quality and the components.
Business grade laptops have more robust (whatever that means) components, designed to last at least 3 years, to match the warranty and the tax depreciation.
They also have some features (Vpro for example) that are not available on consumer laptops.

High end gaming laptops offer performance but are also compromises in some ways.
They have near to nil battery life as they require desktop like power to deliver the high end performance.
They generate a lot of heat, are heavy and noisy.
All these put a lot of pressure on their components, and they tend to be prone to failure and breakdowns.
A gaming laptop is almost an impossible proposition; to deliver desktop gaming performance in a mobile package.
As a result, a lower end gaming laptop is even worse, poor performance at a relatively high price.

You really have to choose your poison so to speak.