In the previous Open Thread, the following claim was made:

I want to emphasize that a transactional attitude toward relationships is itself inherently pathological. Someone with this attitude will always either feel resentful that they aren't getting a better "deal" in the relationship or anxiety that the other person feels that way about them.

This kind of attitude seems to be widespread, but it doesn't ring true to me. Most obviously, I have a transactional attitude towards my relationship with Tesco; this doesn't cause me anxiety that Tesco feels the same, or worry that I'm not getting a better deal. If Sainsbury's offers me a sufficiently better deal, I won't worry, I'll just switch my weekly shop.

But more deeply, I have a transactional attitude towards my relationship with my fiancee. I'm with her because she makes me happy, and because I enjoy spending time with her, and because she seems like a good investment. And I do the same for her. It's a transaction. Now, there is a difference between my attitude to her and my attitude to Tesco, in that I have created a lot of relationship capital with her, so I wouldn't leave her just because of a seemingly slightly better option elsewhere, as I would with Tesco. But that just means it's a long-term transaction. Similarly, I wouldn't change my job as easily as my supermarket, but my relationship with my employer (not even a human being!) is definitely transactional.

It seems to me that every relationship, whether romantic, friendly, business, or whatever else, is, at bottom, transactional; the question is always "What do I get out of it?" It doesn't have to be money, and it doesn't have to be an immediate pay-off, but if it's not there then why are you wasting your time?

Am I missing the point here? Is anyone able to defend the idea that you shouldn't look at relationships in a transactional way?