chewer - someone who chews (especially someone who chews tobacco)

concert-goer, music lover - someone who attends concerts

customer, client - someone who pays for goods or services

imbiber, juicer, toper, drinker - a person who drinks alcoholic beverages (especially to excess)

drinker - a person who drinks liquids

eater, feeder - someone who consumes food for nourishment

prodigal, squanderer, profligate - a recklessly extravagant consumer

smoker, tobacco user - a person who smokes tobacco

snuff user, snuffer - a person who uses snuff

user - a person who makes use of a thing; someone who uses or employs something