True, but I have a couple of things going for me here. First of all, it's occasional use, so maybe a couple dozen hours a month. When it's on, it's pretty much always full throttle (the windchill is like -10 right now). You get the most creosote when you run it damped down and the wood smolders. So I'm hoping to get away with cleaning it once a year. We'll see.
I was all gung ho to get set up in the pole barn, but I've decided now there's no rush. The floor out there is so smooth and clean it's almost a shame to start getting it all oily. It's working great to park the tractor and K5. The garage is already an oily mess and so much easier to heat. I may even put some insulation in it.
If you're building a wood burner, you could do some sort of auger on the bottom to draw the ash out. Just a thought.