Fuel filter & fuel sysetm flush

[MAC]

I need your opinion on fuel filter and fuel sysetm flush. Thanks in advance.

I took the Hummer into the dealer today for 19,000 miles oil, lub and tire rotation, all covered under service contract. The service advisor told me that my Hummer is due for replacement of fuel filter and fuel sysetm flush for $310, which is generally scheduled at 15,000 miles(my last oil change). He explained what they are and I understood, but I told them "it all makes sense, but I'll wait until next time. I have never heard of fuel filter replacement and fuel sysetm flush, let me get use to them first." Honestly I don't remember having these done on other vehicles before, that is dozen cars in 2 decades, sounds like somehthing new to me which it shouldn't be.

What do you think?