Properly sharing is a huge part of living with roommates. You have to share a bathroom, a fridge, a living room, and that’s only the beginning. On some level, I think you should be sharing common household items with your roommates. In my house, I’m the one who buys the laundry detergent, one of my roommates gets butter, and we often split condiments and spices because it makes things much easier. At my last apartment, we all bought our own stuff, which is good if you’re concerned about someone mooching off of your groceries, but bad if you don’t want four separate egg cartons in the fridge (true story). That’s all well and good if you’re working on the honor system (I’ll borrow one of your eggs now, and you can borrow one of mine later), but not every roommate is so considerate, communicative, or willing to ask instead of taking.