As a non believer, do you also reject cultural and social aspects that have religious roots. E.g. festivals, weddings etc.
Most of those traditions and ceremonies existed before religion. The religious just took it over.
The winter solstice was celebrated long before christians got their hands on it. Weddings aka unions have been around in every and aboriginal system forever. Today marriages are more contractual. I don't really know of specific festivals that are religious in nature and if they are, they were hijacked by said religions.