Well I can see how you would not feel very special with the way he presents this "offer". To be very blunt, he sounds like he just wants to get laid. Then when it's time to return to work, everything will resume back to how it's been......and that will cause more emotional frustration for you. I mean, the least he could do is to make some sort of reference to having time for romance.....but he steers clear of it. As usual, he makes it appear as if you are the accessories that come with the job.
Does he need to make a commitment in order to spend a weekend with you? I suppose that is up to you. From the way I read your post, he was uncomfortable just admitting it would be a romantic time for the two of you. I simply don't get it, unless he is afraid you will take it and run with it. He's not ready for that much yet.
I think his way of handling it makes you feel kind of cheap, maybe. You want him to man-up and tell you he wants you, instead of this beating around the bush about it. You may be able to tell he wants you....but a girl just likes to be told sometimes.
But here's the thing, MM. I don't think he's the kind of guy you can try to force him into anything he doesn't want right then. You may wish you could put enough pressure on him that he would at least make you feel you were valuable enough that he won't let a "label" scare him down. I mean, seriously! I believe if you told him "no", he would say "Okay then, cheers!" and be gone on his own. Now, it may cause him to consider that MM has really changed and he needs to get a different game plan, IDK.
I can't really tell you what to do b/c you need to make the decision. If it were me, I would probably tell him, "Thanks for the offer, but I have decided to not tag along on trips with any man who wants to use me in his private times as a tax write off. I find it rather insulting if he can't value me enough to label it what it is, at least to my face. And if this is the case with you.....then you have my answer". But, MM, that's just me and my personality.
I am crazy enough to believe that if you hold out for what you want, he will eventually realize you are not going to settle for his measly crumbs. But if you decide to go this route, then you don't need to play anymore footsie games with him. He may think after the episode in the bedroom the last time, this is the next step. An overnight hide-away that he can count off as a business expense. Who wants to be some man's business expense?
He is not clear b/c he doesn't want you to make more out it. He wants to get laid without a commitment of something more. I think men have been like that since Adam (who really didn't have a say about it..... )
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!