This is a tricky one - my heart agrees with CarolC and my mind with Illuminata, but with some provisos.
Culture is part of the glue that bonds us collectively, and a part of it, for the Anglophone world,is the old Judaeo-Christian melting pot of the King James Bible, the BCP, Shakespeare and a host of other literary and classical references.
Pick up any book of quotations, open it at random and, if you're over 35, you'll find passages that you recognise and which resonate because you've grown up with them. And by far the biggest chunk of any book of quotations comes from the Bible and Shakespeare (as well as good old Anon/Trad, who is all our grandparents).
Thus, even as an atheist/humanist, I'm saddened by the loss of the language and poetry in which I grew up, be it the Psalms, Virgil, Homer, Milton or whatever.
Admittedly my own kids are unusual in that they've been force-fed with the "old mix" (and are regarded as eccentric as a result - but bugger it, my daughter's got an interview for Cambridge next week), but I'm often boggled and depressed at their contemporaries - some of whom can make neither head nor tail of art history, for example, because the classical references are lost to them. Or who think that Michelangelo, Leonardo and Donatello were three bloody terrapins!
And that's where I have a problem with the whole area of cultural knowledge that we don't have, as Illuminata says.
I love the idea of kids celebrating Diwali and Eid, but I get hugely depressed when all they can talk about is Pokemon characters. Fine, go easy on the Shakespeare if you're going to replace it with something equally satisfying (or update it - like the superb Romeo and Juliet by Baz Luhrman - which will entrance the most cynical teenager), but if you're going to do the cultural equivalent of taking away a national dish and replacing it with a Big Mac...
...pass me my Browning!

And yes, I know I'm a snob, but I'm not ashamed to be one in that context.