Shift and Bitpay are the ones I use, Shift to spend direct from funds held in BTC.
I always believe that bitcoin can not be wasted on anything. I know that especially today it is a waste of money, because if you keep bitcoin, then in the future it will bring considerably more income.
Yes its very hard to earn bitcoins so I will never prefer to waste them on buying clothes and instead will use fiat for shopping and keep my bitcoins intact in my wallet for the future as price will be much higher in future so keeping them till that time and selling at higher price is the best thing to do with bitcoins.