Yes, you tie yourself somewhat to games that you like. I think it's because they do things that you like, implement good mechanics, have good characters, whatever. If that's the case, why is it strange that you are also tied to things you dislike because your values are not fulfilled by that thing. Someone liking a game you dislike is essentially committing the same 'crime' someone disliking a game you like is, if they like it for reasons that correspond to the reasons you dislike it. I think in the end it comes down to self-interest. You don't want to see people praising things you don't like because you don't want to see more of that thing as opposed to things you do like. For example, I don't want to see people praising linear shooters and trashing sandbox RPGs because that contributes to getting more linear shooters and less sandbox RPGs. I think that's fine, and that's why I have a reaction when someone likes something I don't like. Another example, ME3's ending. It's fine that some people liked the ending. I hated the ending because it contradicted everything I thought I had invested in the series. If people are praising the ending and that's all Bioware hears, they're going to get the impression that it was well-received. It was only because a lot of people who hated the ending spoke up that anything, however inconsequential, was done about it.
Although I will say that in situations where you have no investment in the thing someone else likes, that's less justifiable. For example I'm at the point where when I hate music from a certain person or group, I realise it's because I'm not the target audience, and since their target audience does not overlap with the target audience of music I do like, it's fine that it exists and that other people like it.
tl;dr: I see openly criticising or praising things as a way of showing your preferences in the hopes that will be considered by content creators as part of the larger market.
Although I will say that in situations where you have no investment in the thing someone else likes, that's less justifiable. For example I'm at the point where when I hate music from a certain person or group, I realise it's because I'm not the target audience, and since their target audience does not overlap with the target audience of music I do like, it's fine that it exists and that other people like it.
tl;dr: I see openly criticising or praising things as a way of showing your preferences in the hopes that will be considered by content creators as part of the larger market.