On 26/06/2014 14:13, tim..... wrote:
[...]
you can't put you non-Oyster card in an Oyster wallet.
You'd never know which was which

Never heard of marker pens?

rubs off

Use an indelible one.

still comes off (eventually)

If this is genuinely your complaint then may I suggest you don't use
public transport at all, because it'll confuse you too much.