There's just the two of them, and I don't think they use a lot of eggs. But yes, evidently they will occasionally buy store bought eggs. I think they (her husband moreso than her) prefer fresh eggs to store bought though. The thing is, I almost never give them the large eggs (because my husband sells them to his coworkers). I give them bantam eggs (which is what we as a family eat, to reserve the large ones). They KNOW I don't sell the bantam eggs...that I use/cook with them.
My S-I-Law's husband told hubby that "family comes first" when dh mentioned to him last week (after being asked if we had eggs they could have) that we're barely getting enough eggs to sell to his coworkers. So I do think he believes he should not have to pay for eggs, since we have them and we're family... I understand his mentality - because I think he was raised to "share what you have." But someone offering to share is different from going asking/expecting...