If you work at a place like that for that long, I'd think it's safe to say that, eventually, one of your customers might mention the fact that it's not their first marriage. Even if that doesn't happen, you can't claim total ignorance - you have to know that, eventually, you're going to sell a cake to someone who's been divorced. Given how prevalent divorce is, it's unavoidable. By the same token, if you're a Christian who sells condoms, even if you're not a Catholic, you're going to eventually give one to someone who's single and will use it for extra marital sex, which is supporting sin.