I don't know about anybody else, but for myself, especially with Firefox mobile with its tab previews it helps remind me to check on websites that I would forget exist if they're a bookmark because they're right there. I use bookmarks to get Firefox to autocomplete urls I visit frequently and for tabs I'm no longer using but may want again in the future.
On my phone I also have open a bunch of tabs.
That's trus.
But not on my desktop