I'm not really spending them anymore. I spent a lot of them monthly when I was mining Bitcoin. I paid as many of the mining bills as I could using Bitcoin. I even bought box fans to blow on the mining rigs using an Amazon gift card from SpendBitcoins. Now that I don't mine anymore I hold them. I know I should spend them and replace the ones used but that's too much of a hassle and I'm lazy.
Coinbase has a feature that is called something along the lines of spend and recharge. It allows you to buy something with bitcoin in your coinbase account from a merchant that accepts bitcoin then coinbase will purchase an equal amount of bitcoin for you (debiting your bank account) so you end up with the same amount of bitcoin.
I think this is actually quite smart on their end because they would be making two fees, one from you repurchasing the bitcoin from them and one from the merchant.