It's definitively a small luxury item, but can't really argue with anyone's spending habits. More relevant, "cups of coffee" is not a good unit of measurement

It's definitively a small luxury item, but can't really argue with anyone's spending habits. More relevant, "cups of coffee" is not a good unit of measurement and can be misleading. Just say the number and trust that people can cope. Other offenders: Measuring distance in "cars lined up from here to the moon", expressing data in "Libraries of Congress", or expressing cost in $/day instead of $/month or $/year.