For use, the most significant "yes" has been travel. We knew we'd live in Europe for 2-3 years, and while we are here and getting to so many places is not only relatively cheap, but also possible with little or no vacation time, we wanted to make the most of it. We just hit 21 months and 25 countries in that time, with multiple trips to many of those countries. While we haven't traveled extravagantly, it has been a lot of money. Working an extra few, or even 5 years has been worth it, if it comes to that. I don't think it will since DH is someone who likes to work and I suspect the FIRE point will be blown past, with him still working for years.
When we were in (and when we soon return) to DH's brutal schedule of sustained 110+ hour weeks, there will be no time for travel. At that point, out biggest splurge will probably be conveniences, so that his very limited time can be spent in a way that lets him get some rest and relaxation. If that means paying a kid to mow the yard sometimes, that's fine with us.