Sunday lunch

I have two blackbirds (specifically a blackbird that is black & a blackbird that is brown, so I am assuming they're Mr & Mrs - or they may just be co-habiting).
But I digress talking about their relationship status.
They regularly 'dine out' on my lawn when it is wet (should I charge a weekend surcharge?)
Sunday lunch today was worms once again - they never seem to order anything else off the menu.