I work as a freelancer (Europe) and I think I work reasonably hard. But is really difficult for me to honestly log more than 10-15 dev-billable hours during the week. The rest of the time is spent in chat and learning / playing with a new things.
Do your clients understand that playing / trying out new things leads directly to you building the finished product?
Or is your playing truly separate from any of your client work?
My max was 48 hours/week ( but this is an exception )
For living I build e-commerce solutions and backend stuff. And in free time I play more with a frontend. Recently with react/redux and in the long run with every possible new technology on the horizon. I guess I waste a lot of time doing this as most of these things isn't immediately related to client work. ( but over time It helps me to sell to them a few ideas for improvements )
Also, I track my time and habits in detail ( using rescuetime ). Probably without such careful loging I would overestimate how much time I am spending on actual coding.
I live in Warsaw and live here is a lot cheaper than in Western Part of Europe. My clients are Canada / UK based and I charge between $50-$70/h so even 10-15 hours a week is enough to make living over here.
