I've definitely made my peace with it. Think of it this way: how much better is a bunch of imports than the slew of stackexchange copy-pasta you'd find in an old PHP app?
(moment.js supports a huge number of localizations, which is impressive and good for i18n. so in this case maybe it isn't directly comparable to copy&paste for anything but trivial use-cases.)
My rule in code reviews is if you're basing/copying something from the internet, you better be able to explain everything it's doing, and if you're pulling a dependency you better be able to explain why we need it and why you think it's trustworthy enough to put in our application.