I think Paul’s words; “weak in the faith” can be easily taken in the wrong way. It doesn’t mean that the person is a weak Christian. When I was newly saved (about a year and a half) I was transferred to England. I was a guest at French people’s house. They were from Paris and lived in London because of business. The lady of the house put wine for a drink on the table. I had been a kind of slave to alcoholic drink before salvation. I politely told her about this and asked if I could have something else. She went and got a soft drink. I don’t know whether I could have labeled myself weak in the faith or not.
These verses speak of meat offered to idols and then sold in the meat market. A person newly saved, or even longer could have a conscience about it. Another believer could see nothing against it at all. There could be disputing’s about it which would not be good for the Church. It could disrupt the whole Church. There may be many such things as this that could happen.