Absolutely. I truly enjoy the hobby, and it's the only hobby I've ever had that paid for itself (unless you count putting meat in the freezer from hunting). If I crunched the numbers, I'd wager my buys and resells resulted in at least a 25% cash profit OVER and ABOVE the pipes I kept out of the lot for myself. The only book I ever bought on the hobby was the $20 PIMO's Guide to Pipe Crafting at Home. I bought a few specialized tools, stains and chunks of wax from PIMO, but those expenses were probably recouped in the first six months of me reselling pipes.
Now I'm not suggesting anyone quit their job to refurb pipes (though I would love to do this full time) but as a hobby it can definitely pay for itself - and put a few nice pipes in your rack.