At least as far as Wrigley Field goes the Wrigleys owned the team as well as the ballpark. If you own the real estate then one of your property rights is to name the property whatever you want. The thing about modern sports facilities that is offensive is that the taxpayers own the facility and pay for its upkeep, and yet there are sweetheart deals where the tenant/team gets the income from the sale of the naming rights.
Wrigley Field in Chicago was first named Weegham Park because Weegham built the park in the 1910’s for his Chicago Whales franchise in the old Federal League. Way back then it was not uncommon for the team owner to actually use his own money to buy the land and build the stadium. Example: Ebbets Field in Brooklyn, which pre-dated Wrigley Field, was built by team owner Charles Ebbets.