AITA for not giving MIL a mask that I brought for my daughter?

My wife and I are visiting our daughter at college for a couple days, she’s a freshman and we haven’t been able to visit her much in the last couple of months so she’s getting a little homesick. My wife’s sister lives nearby so they are also coming to visit their twin daughters here. Now obviously because of corona we all have to wear masks, the school has a policy of no mask no entry. <br><br>We all met up at the dorm and my wife’s sister and her husband were taken aback that we were wearing masks. They don’t believe in the virus at all and never wear masks. They say that this is a trap by the government to control our lives and we shouldn’t fall for it. They didn’t even wear them on the plane or at the airport. They were surprised we did. They did bring two masks with them, one for each of them but they didn’t bring one for their daughters. So when we were walking towards the dorm they asked if they could borrow two masks, one for each of their daughters. <br><br>I said all we have is the two that my kids are wearing and the one I have for my daughter incase she loses hers and I’m sorry but I didn’t pack extras. They asked me if I could just give her the one I brought for my daughter and I said no. They said I don’t get it, I can just go home and get another one while their daughters have to go back home, they were on vacation and have no time to get their daughters masks. They then said that I’m causing a family rift by not helping them out like this. I told them that this is not my fault and that I’m not going back home just for this.<br><br>They called me an asshole for this.