I'm with Mummytime - Jill may be happy to do the washing up, but I really think that after she's prepared, cooked and served up a large meal for 8, basic good manners demands that the family should have insisted on doing it.
Yes but ... it all started from Jill's irrational hatred of Toby, based on what Grace/Robin did 60/30 years ago.
Rational or irrational, Pip had no business just inviting someone to Jill's birthday celebration without checking, and, whether rational or irrational, surely her views should have had priority?
I would say that going by what Jill actually knows of Toby, her feelings are verging on irrational - although of course she's going to be proved right in the end.
We don't know how much she knows. She might well have heard at some point about his general unreliability with the poultry - I suspect Josh would have ranted about it in her presence - and she certainly knew about the gin brewing thing and was entitled to be very unhappy about something that could have resulted in David and Ruth being prosecuted.