If you go outside, you need your wallet - we get that - it probably has your ID in it, and you may need that but do you REALLY need to carry everything else, ALL the time? Take any credit cards that you don't need all the time OUT of your wallet and keep them at home - by not taking them with you when you go out, you wont be able to use them and this can help you reduce the urge to buy that thing, that you probably don't need anyway!
Here are a few things that you can do with credit cards that you are not carrying around all the time...
1) Freeze them in a bowl of water in your freezer - by doing this, you will need to thaw them out before you can use them - most of the time the urge to spend and buy is gone!
2) Give them to a TRUSTED family member to hold on to for you - and tell them that you only want it for urgent matters - always helps to have a buddy system and help each other out.
3) Cut them up - yes, if you don't need multiple credit cards get rid of them!! - once you have destroyed them, you MUST contact the issuer and have them actually cancelled - having a single credit card is convenient but in some cases having multiple credit card lines showing on your credit can have a negative impact on your credit score and lenders may not want to lend to you, or they may not give you the best possible interest rates.