I hate to say it, but there are a lot of people who don't pay attention to the religious holidays of religions other than their own.
When I was in HS, and working nights at a grocery, I would say "Merry Christmas" to the customers as they left. Everyone in our store did it. One night, a woman with an adorable little girl (age 4-5) came through I wished them a Merry Christmas, the mother thanked me, the little girl said "Oh, we don't have Christmas. We're Jewish." The mother quickly bent and started to reprimand her daughter, and the two bustled out of the store as quickly as they could while I called "I hope you have a great Hanukkah!" while furiously trying to remember if Hanukkah had started already, or was going to soon.
At the time I didn't understand the woman's actions, and her overall mannerism when her daughter said that; but, reading this thread, I have to wonder if she had met someone like OP's gas station self-appointed missionary, and wanted to avoid any further attempted conversions.