i would make the ribs as best as i could this time. who knows, they may have something cool in return. they could be that generous. if they just consume them and only invite you to join them for dinner, that would be a red flag, they are just assuming you love to cook so much that it is fun for you and less work for them.
if the latter is the case there is still no reason to make enemies with them or be rude. just wait until they dump another huge task on you. do what you want with what is given. when they come by to collect their bounty simply infom them another nieghbor smelled the cooking, came over with some friends and ate it all up. of course they would understand being so generous and all.