It might not seem like work, but being a professional pilot is no walk in the park.
As a very new CPL and FI(R), I have to agree with that. I'm still at the point where it's all new and exciting and I can't believe I get paid to fly. But walk in the park it is not! When you're a PPL, you fly when you want to, when you feel like it, when the weather is nice - it's only down to what YOU want. The very moment you start getting paid to fly, commercial issues come first. I was doing trial lessons last Saturday, with a nasty wind 14kts gusting about 28 and changing direction all the time. I was told to take up this succession of people for 0.4 hour trials, in an R22 which gets thrown around by the wind, to get back on time, and don't scare them! Not easy (at my level anyway) and doesn't fit into most people's definition of fun flying. I enjoyed it actually; must be a masochist or something. Actually, what I enjoyed was proving that I could do it; the satisfaction of a job well done.
But the point I'm making is that unless it actually got to the point of being dangerous, I couldn't turn round and say that actually I didn't like the weather and didn't feel like doing it. And that's something that no-one pointed out to me when I was a starry-eyed PPL thinking it would be great to get paid to fly.