Intel doesn't recommend/market Xeons towards everyday users because it is not a consumer chip. it is demonstrably more powerful than their equivalent i7 chip, but at the cost of having a server-oriented feature set (no graphics capability and added Virtualization, support for ECC RAM, larger L1 caches, far more cores, etc). The chips are also typically far more expensive than their consumer counterpart which is why they are aimed at companies that can afford it.
For a standard consumer purpose- such as playing a game- a Xeon's capabilities will not tend to lead to it performing much better than a similar i7. However in the context of, say, game servers, the added cores and L1 cache would certainly lead to better performance of the server, in particular when running numerous such servers. The entire point of the processor is for running server software, after all.