I've been staying with Firefox not for the performance (today Chrome loads Google sites like YouTube faster), but mainly for Tree Style Tab extension. I couldn't imagine opening more than a dozen of tabs without it.
I can't imagine having more than a dozen tabs open, period. You tab hoarders will never make sense to me...
For games, I often have a bunch of wiki tabs open at the same time.
Fortunately, I also habituated the simple behavior of "If I realize I have a lot of HN tabs open, right-click and close the entire pane". That's how I know I'm clocking about 100 tabs per two days on HN alone.
Also, Sideberry changed my tab hoarding habit in a way that still results in keeping hundreds of tabs, but using them in much more sensible way. I keep them arranged in trees stemming from topical groups on high-level panels, and trim or kill as they're no longer useful. Most of those tabs are unloaded anyway, but the interface works as excellent short-term (days to weeks, sometimes a few months) bookmarking system - and I don't lose tabs anymore (as in knowing the tab is there somewhere, but not being able to find it in the vast sea of other tabs).