Indeed - in theory I shouldn't feel guilty, I totally agree that logically it's just another one of those tasks that you're paying somebody else to do. I can't believe there is a person in the developed world that doesn't pay for somebody or for something to do something they theoretically could have done themselves. Cleaning is something I really hate doing, same with DH, and I cheerfully pay other people/other things to do things I don't mind doing on occasion, so what's the issue with paying somebody else to do a task I loathe?
I think with cleaners though, it's so much more personal. They're in your home, picking up your things. With a takeaway you don't see them cook it, they just deliver it and the interaction is minimal. A dishwasher is an inanimate object you don't feel bad for it "slaving away" making your dishes shiny. Whereas a cleaner is a real human being in your home, and even if they're being paid a decent amount, it's still unnerving seeing tasks you know you could have done and are really your job, being done by another person. Especially as most people have it drilled into us by our parents to clean more - there's a lot of repressed guilt there I think!
I admit I have to be out the house, I feel terribly guilty about it even though right now I physically can't (36 weeks with DC4, with bad SPD, DH working long hours and too exhausted to clean too) I usually try and be in when they arrive and have a friendly five minute small talk exchange so it doesn't feel too impersonal, and I always give a couple of quid extra. But my conscience is still screaming blue murder at me so I need to get out - DH feels the same!!
So so so so glad we have them now though. As I mentioned before, it's made a huge difference to our lives, I'm not so sure we could have got as good value for money out of anything else in terms of life improvement. It's really helped with my depression, and DH's grumpiness levels and as a result improved our relationship. We're extremely lucky that we're finally in a position where we can (just about!) afford it. I need to get over my guilt!