Antonyms for 'buying for' can have different meanings depending on the context. Instead of 'buying for', you could use 'selling' or 'discarding'. If you're referring to the act of purchasing items for oneself or someone else, antonyms might include 'returning', 'exchanging' or 'donating'. In the context of shopping for groceries, antonyms could involve 'cooking from scratch' or 'growing your own produce'. Alternatives for purchasing in bulk or stocking up might include 'downsizing' or 'minimizing consumption'. Ultimately, antonyms for 'buying for' will depend on the particular situation, and other words with contrasting meanings could be used to convey the desired sense.