Does it really matter? Like all you want not going to hurt that many peoples feels.
If I really liked what someone responded I would reply to it or carry the conversation into a message. The like button for posts is more of "I agree with your stance on this and I have nothing else to add to your statement at the moment" button.
Randomly liking all posts from here on out. Or not.
I only click "like" to the ones I like.
To each his own.