The cell tower leasing consultants they hire are very charming and friendly and may remind you of you brother, cousin or child. Some are fine people who are just doing their jobs. Many of them are sharks who smell a quick buck and would shove you down a flight of stairs for a nickel. Either way they do not work for you... They are hired guns that work for the carriers and the tower companies.
In many circumstances the reason for disclosing the information is because the other party has the strength and ability to take the idea forward; the missing piece of the puzzle is the actual business concept. Business concept owners are often fearful that by disclosing information to a second party will result in that party taking the idea and developing it to commercial realty without them.