I don't see anything wrong w/ not splitting the bill in some situations. My gf is allergic to alcohol so is it fair for her to always pay $5-10 more at every group dinner because it would make it easier for everyone, even if it's not that much $ each meal?
Btw young people nowadays use venmo to great effect...as I found out when I suggested c4est's strategy and everyone looked at me like I was calculating shit with a friggin sliderule.
If there's a large discrepancy, then of course it's a different story. I wouldn't expect someone who doesn't drink to split for the alcohol. My post mainly refers to people who are like "I didn't eat any of the queso" or mine was only 8.50 and yours was 9.75, etc.