This is an emotional manipulative tactic, and not a great look. It's no different than calling copyright infringement "theft", abortion "murder", or someone who speeds a "criminal".
Note that you're not wrong. People that get cranky if they don't get enough caffeine are probably feeling some withdrawals from it, and caffeine is a drug, but calling those people "drug addicts" leverages the emotional connotation from it's more colloquial usage. If you can't support your stance without emotional manipulation, you don't have much of a stance, yeah?