The word 'work' comes with a lot of baggage. It instantly conjures the image of someone physically or mentally toiling at some task until it's thankfully over. This association comes from the most common form of work, a job that provides money for yourself and your family in exchange for your time and skills. There's a misinterpretation that occurs when we describe creative activities as work because of this.
To the creative while the tasks they do are most certainly work it's not as taxing as other forms of labour. It's work borne out of an innate desire that goes beyond the tasks to get it done. Building a side project is filled with a ton of menial tasks that few would do for free but many choose to in their spare time. Many do without any immediate financial incentives. It's as much a hobby as it is work.
Vocation is a more apt description. The word originates from the early 15th century and references the call by God to the priesthood. Creative work is a bit similar. It's an inner call to create in whichever medium you prefer. It's work but with a motivation that comes from within and not just as a requirement to live. Being able to live off your vocation and not just work, that's the ultimate goal as a creative.