Is this a ground lease? If not, then it is not comparable. The Boy Scouts would be within their rights to demolish the building when they left; your tenants are not.
And commercial vs public-non-profit is apples v oranges.
The City is getting a great deal with the $1 ground lease of the building, benefits to the community way beyond the minor subsidy on this ground lease.
Okay, so let the Boy Scouts save the city the expense of demolishing the building and then the city could sell the land for its market value.