Oh, there's a fairly established market of fursuit cleaner/fragrances that are a mixture of alcohol and scent. Some of them smell really nice (think Bath & Body Works, not high class perfume). There's also been a lot more attention given in the past decade or so to making washable suits. You'll definitely get people who smell like an anime convention, but at this point it's by choice and not because suits are uncleanable. But if someone is taking normal care of their fursuit you should only be able to smell it if you're actually wearing the head, which is a pain to clean.

For real, fursuits are basically heat traps and the air in airplanes isn't exactly the best. Not to mention no access to showers in the plane (frequent showers are a must if you wear a costume) makes it even worse

Opened the thread just to say "can you imagine the smell on that plane?"