Depends on your local laws. Verbal contracts exist here but they are unenforcable without a 3th party witness and even then very limited and only used for the simplest and most immediate exchanges. Buying and selling is kind of a contract but only handled in courts if it's between individuals, if a company is involved then it's the consumer protection laws and agency that handles that. Most obligations and privileges from buying and selling are handled by local law instead of a contract. But contracts on the Internet are only legally binding if you digitally sign it here, an agree button or even a normal signature isn't binding here for that. Our government IDs allow for online signatures with cryptographic keys unique to each person, that's the only legally binding online signature here.

A TOS can only be used to enforce your behaviour on that platform, anything beyond that is not enforceable here.