They are buying them for the same reasons people bought BTC when it was under $1 or $10 or $30 or even now, for the most part.  Merchant adoption didn't drive Bitcoin, speculation did.  A bit silly to be getting all "high and mighty" now, don't you think?  

Embrace that the crypto-space as a whole is growing.  That's more important than any single crypto-currency and that includes Bitcoin.  People moving away from government fiat, is all that matters in this equation.  People would be wise to remember that.