As has already been brought out on the two previous threads, it is a simple zoning issue.
~Sue
WHAT IS A CONDITIONAL USE PERMIT?
A CONDITIONAL USE PERMIT (CUP) allows a city or county to consider special uses which may be essential or desirable to a particular community, but which are not allowed as a matter of right within a zoning district, through a public hearing process. A conditional use permit can provide flexibility within a zoning ordinance. Another traditional purpose of the conditional use permit is to enable a municipality to control certain uses which could have detrimental effects on the community (Neighborhood Action Group v. County of Calaveras (1984) 156 Cal.App.3d 1176).
Consideration of a CUP is a discretionary act. A CUP application tendered by a project proponent is considered at a public hearing and, if approved, is generally subject to a number of pertinent conditions of approval. Depending on local ordinance requirements, hearings are typically held by a board of zoning, the planning commission, or a zoning administrator. The owners of property near the site are sent advance notice of the date, time, and place of the hearing.
Examples of common uses allowed with a conditional use permit can be found in any city or county zoning ordinance. For example, Santa Rosa's zoning ordinance lists uses which may be permitted within single-family residential districts with a conditional use permit. These uses include churches, public or private schools, public building or utility structures, parking lots, temporary subdivision sales offices, and community care and health care facilities. Chico's zoning ordinance lists various uses permitted with a use permit issued by either a planning director or planning commission. These uses include temporary amusement attractions, the placement of a building or structure on a lot or parcel which has been moved from another lot or parcel, public buildings and facilities, parking or access located off-site from the site being served, private recreation centers, and planned developments. Each city or county may include in their zoning ordinance a wide variety of uses which they will permit with a conditional use permit.
(More at link.)