The simple answer to this question is, yes, most swingers I know, whether a couple, or single for that matter, would be offended by someone who assumed they were somehow "special" and expected to be treated with "generosity". And no, I am not trying to attack you personally, I am simply trying to help you understand an important distinction between what it is being a single and dating, and what it is to be a swinger.
You are either a swinger or not, whether you are single or a couple makes no difference, a swinger is a swinger.
So if you want to be wined and dined, stick to dating other singles. If, on the other hand, you like casual recreational sex with others, don't expect to have the other pay your way, or even offer to. Because you need to understand that they believe you are doing it for the same reason they are. Therefore, it would never occur to your average couple that they should offer pay your way. And it would seriously insult them if they new that you expected them to make the offer.
In fact, once you gain more swinging experience, you will probably find that it would be insulting to you if someone did offer to pay your way. The reason for that is that it implies that they are trying to buy your services, or make you obligated to them. And whether they admit it, or even realize what they are doing was trying to make you feel obliged to service them, or not, at some point, that is exactly what they would be doing.
It is one thing to buy somebody a drink or cover the dinner check without any expectation or obligation. But once you start having someone pay for your hotel room, travel expenses, or any other large ticket item, you are going to be, or at least feel, obligated to them. To often in swinging, once you get to the play room, you will find yourself in a play situation that isn't working for you. At that point, the last thing you want is to feel obligated in such a way that you can't just politely leave.