Adelaide Oval is so expensive to purchase food and...

Adelaide Oval is so expensive to purchase food and drinks. I love to have company of my family with me but it is just to expensive by the time the entrance fee and consumables are charged and paid for.
We have tried and suggest to bring in your own keeping in mind your bag will be checked at the gate.
Also can't use cash to purchase items anymore, have changed over to credit cards only.
This is impossible for the likes of myself who doesn't have or use cards as payment for purchasing.
They can not refuse cash monies as it is legal tender under the law as a card is only a transaction device to say monies can be taken out of a bank account.
It is a shame that these thing take away from the enjoyment of the venue and whatever the performance maybe either sports or the arts.
In reflection it is a beautiful venue but to expensive for the pocket. One can only hope prices would be reduced which would then allow more to visit and spend rather than bring within their bags.
Maybe also stop people from getting to the oval so early obtaining and saving a seat by leaving items on them and venturing out to a nearby hotel, cafe etc for food and drinks before the start of the games. This good for the outside hotels & cafes but the lose in revenue for the Adelaide Oval venue.