Just completed some freelance work writing a non-fiction academic book chapter. Not exciting stuff, but it was good to stretch the legs in a new environment for a while. Of course, seeing a few dollars dropped into the bank account was pretty good too. As John Birmingham says, 'Writing for love is nice, but getting paid is even sweeter.'
I used to worry that writing schlopp for a living would negatively impact my fiction. That hasn't turned out to be the case. In fact I think working your arse off in a piece with which you hold no affection is actually a good way to reaffirm your love of writing incredible fiction simply for its own sake.
And quality schlopp itself is a noble quest as well. The world runs on it after all.