As a kid, were you ever emboldened to jump ramps with your bike by watching Evel Knieval? I don't mean little ramps. I mean something really daring? Something you truly did not possess the ability to do?
Then boom. Wrecked bike and broken collar bone, not to mention the bruising and the missing skin.
That's what it means to cause a weaker brother to offend. He wants the faith to do things that he just can't do, but doesn't really have it. But wait, he knows that the one that he looks up to as an example and a teacher does so all the time (or maybe it's an entire congregation) with a perfectly clear conscience. So he tries it. Pulls a chair up to a table right outside the idol's temple. The meat is fresh and savory, but as soon as he sinks his teeth into the succulent steak, his conscience is violated. His brain is telling him one thing, but his heart another, because he still has a conscience toward meat that was offered in sacrifice to an idol as an evil thing.
Because his act was not of faith, he sinned. And because the stronger disregarded his weaker brother and put a stumbling block in his way, he sinned as well.
Now, one man may have a conscience toward wine as an evil thing, but he has a strong conscience, and is not emboldened by your liberty to do something he thinks is wrong. You're not wrong to drink whether in front of him or not. You're wrong to call him a moron, and he's wrong to judge you.
See how different that is from the usual misconstructions of the passages into what you and Rick are asserting? We can take it verse by verse if you wish, but we will not talk about monkey butts. We will talk about meat and wine.