How so? A 1kps contribution should make it pretty obvious that you're only after the table scraps that would otherwise thrown away.
Of course, it is obvious a player adding 1kp is looking for profit with the lowest possible investment.
My Fellowship has optional swap threads and very few participate, the majority of us just post in the chat when we are nearing completion to let members know there are chests available. If there are chests left when I am ready to upgrade, I encourage donating 1kp to avoid wasting the chest. Interestingly, unless there are very few kp left no one ever contributes 1kp. I do not have a problem with anyone profiting from chests on my wonders, and no one is required to contribute. The 1kp in itself is not what I find rude, rather it is the lack of wanting to help your fellows or neighbors - your only motivation is to grab what you can for yourself.
The chests only go to waste if no one knows they are available. Rather than staying silent to snag a chest for 1kp you could let the Fellowship know there are chest available when you see they are almost complete. If you let the fellowship know the members will claim them - as you can see in the screenshot of my chat. I think you are aware the chests will be claimed if your fellow players know they are available, yet rather than be a positive member of your fellowship you choose to let chests go to waste so you can get as much as you can with your 1kp.
I had a player in my fellowship that dropped 2kp on all the AWs in the fellowship and one member was pretty offended and posted in the chat - not naming the member, but everyone knew who he was referring to. I replied that I agreed it was rude, but not to worry because the member would likely not receive help, and he stopped his predatory behavior. Though it is not required in our Fellowship if he had continued, I would have removed him, because his behavior was toxic to the fellowship as a whole.