I am always amazed at the sense of entitlement that some pet owners have. I have a long-haired cat, a long coat german shepherd and an african grey parrot.
My cat and dog are never in my sewing room, but my parrot and I share the same room. So, yes, there is a parrot "feathers / dust" in the room, and I can pretty much guarantee that it will be on the fabric, quilt as I am sewing.
I would NEVER and I mean NEVER expect someone who has pet allergies to work on my quilt. Especially from my house! There is probably very little to no cat / dog fur on the quilt, but there is transfer from my clothing I'm sure.
I'm also a smoker. However, I only smoke outside, and I always wash my hands when I come back in. I don't like the smell of it on my hands LOL I have been smoking for 35+ years, and have not smoked in my home for at least the last 20 years.
It blows my mind to see / read about how rude some people can be and their completely unrealistic expectations - especially when you are donating your time!
Please, stand up for yourself - your health. Explain it nicely the first time, and if you have to repeat it a second time, tell them you're done. Your health is much more important than someone having a quilt completed for free.
Good luck!