Why can't you earn tickets instead of having them put on a game card?

It's a long term investment on their part. By conditioning children now to use "credit cards" spending a fiat currency that someone else provided them with, future adults will be more willing to pay exorbitant amounts for their children to be entertained at these venues regardless of affordability. I definitely agree with you that it's more satisfying to walk up to the counter with fists full of hard-earned paper tickets and trade them trinkets and candy. There was the real lesson for children. It took a lot of planning and work to save enough tickets to get anything significant.

Card readers are cheaper in the long run and less waste

Probably alot cheaper then 1000s of rolls of paper tickets dispensing out of the machines. What's the diffenece?

Cheeper for them not to buy tickets to throw away after one use.

Because the machines all have card readers and no longer have ticket dispensers.