We just started sending DD to daycare the other week and I spose we don't really *have* to. My mum has looked after Natty on my work days for the last 6 months. And FIL has had her on occasion too. But it became a hassle when mum planned to go on holidays etc, so I decided to just send her - seemed much easier to do so.
I've got her in two days/week, so can't comment on the one day/week thing. We're still adjusting/settling in
I don't think you're lazy at all. I have noticed a change in Natty already. She is heaps more confident with the other kids at playgroup (she used to rarely let me out of her sight, and would often cling to my leg the whole time. And this is the mothers' group we've been with since she was 3 months old!) Now she is comfortable for a bit longer, though she still likes to have regular contact with me. So the social aspect of it has already been a big plus for her.
And the snotty nose thing... You just can't escape it, Babes. She'll get sick. But it's gotta happen sometime.