I never spend Comix to get rid of tasks either. You’re right that they’re too valuable, especially since the expansions started costing Comix.
Actually… sometimes i just ignore Puke Boy and let him whine. His puke puddles are easy XP (earn over 1000 XP for a few seconds of work, if you speed up the cleanup) so I’ll just have Joss Whedon cleaning up puke the entire time. Yeah, the attendees are a little unhappy, but as soon as Puke Boy goes away, they get happy in a hurry. You can pop the XP from some superfans if you need to do so to get everyone hyped again. Heck, my con is so big that even if I’m looking for the pills, half the time I don’t find them all before the timer runs out anyway.
Do you have a lot of cash? If you want more Comix, buy 5 blue bags for $20,000. You will get an average of 2-3 Comix every time you do this, plus you’ll earn $3,000-$12,000 of your cash back. That’s where about half of my stash came from. 😉