ICE began in 2000 as an electronic energy platform and grew by acquisition, taking in the International Petroleum Exchange in London and the New York Board of Trade. That is why brent and gasoil settle in London while coffee-futures, cocoa-futures, sugar-futures, cotton-futures and orange-juice-futures settle in New York under the ICE Futures US banner.
For a trader the practical differences from cme-group are separate data fees, separate clearing, different session hours and its own limit rules.
Example: a crude trader watching the brent-wti-spread is pricing an ICE contract against a CME one, with different expiry calendars and different closing times.
Related: cme-group, market-data-fee