I don't think it's a bad thing, it sounds reasonable. To be 100% I would just ask your other parents if they are ok with the situation as it sounds like it's making you uneasy.
If you have there ok then I think your fine.
The law is somewhat unfair as I have a friend who has 5 kids of her own who runs a daycare and that puts her at 10 kids a day and that legal? Bizarre!

I know I would be uncomfortable with that many. I have 90% part time kids and do my best to always keep my numbers to 5 but there has been the odd day where I have gone over for a few hours.

Just make sure that your covered for summer break.