Here is a scenario: If you donate to someone through a page with no reference to the terms of service (no tick box or link) on that page and sent a message with the donation through the same page. Does that message that is being sent with the donation have to comply with the terms of service?
At what point can someone be held accountable for the terms of service?
In the scenario you gave above, it is unlikely that any terms of service would have applied. This is a basic question of contract law, in terms of when and what was the offer and when and what qualified as acceptance. Generally, the offer incorporates the terms of service as a fundamental portion. Providing the tick-box acts as a way for the offeror to have you acknowledge your agreement to their terms. Here, if there were never any terms of service provided to you for your review, then they could not retroactively claim that terms of service had attached.
Have a look at What is a contract and what is required for them to be valid?.
It has been held that if the terms of use of a website are not sufficiently prominent then they fail for lack of consent: you didn't know so you didn't agree.
In addition, if you really "gave" money, as in donated it, instead of supplying it in return for some goods or services (like access to a website) then there is no contract for failure of consideration: they didn't give you anything in return. If they held out that they would use the money for a charitable purpose and they didn't, then that is fraud but it's not a breach of contract.
