Most parents aren't looking for the company to pay for the daycare, although I'm sure they wouldn't mind. I think that what most parents are looking for is to have their kids close and feel that they have more control over their children's environment.
The sponsored daycare could be located in a Mall or other nearby building.
There could be a volunteer parents group to help plan and participate in activities.
Opportunities could be provided to eat with the kids.
The employees of the company may be able to provide technical expertise.
Old and used equipment (computers, chairs desks) could be donated by the company.
Supplies could be purchased cheaper using the company's buying power.
I'm sure there are plenty of other people who could expand on this idea.
This option may be more appealing to a company than a company owned and managed daycare?
This is obviously not economical for small businesses.
Reward: Hearing or seeing the idea in practice would be nice.