usage of pay vs pay for

does anybody know where I can find a detailed explanation of the differrence between the usage of pay and pay for?
even though I understand the basic difference that you pay a bill and you pay for an item you purchase there are some cases when the difference becomes blurry to me (and forget about paying for mistakes you've made) I am more concerned about the other usages. For instance do you pay the tickets you get or do you pay for them?
Thank you very much
Pablo

[Tdol]

You pay people (give them money) and intangible things like bills and taxes, where all you receive is a receipt. In the case of tickets, you do actually receive something, so I'd pay for tickets. I'd just focus on what you get in return for the payment- a ticket is just as tangible as a bag of groceries.