Dear Thieves: Sorry I left you such scant resources for a London trip

Thieves broke into my locker at the DUBUQUE COMMUNITY Y last evening and snatched my WALLET.
Pity the perpetrators: It's packed with more sentimental than monetary value (unless they really planned on filling some prescriptions with my not-yet-activated Flexible Spending Card).
Instead, the wallet contained one of my two remaining £5 NOTES from my London trip (that was the only money in it) and a used OYSTER CARD with about a day's worth of London Underground travel remaining.
So you see, thieves: You went to all that work stealing my wallet, and you won't even manage much of a London trip out of your endeavor.
Where did you get the idea that crime pays?