Truth is, tomatoes are just climacteric fruit; like bananas and persimmons.
|Ripening hachiya persimmons|
So, at an industrial scale, climacteric fruit ripening can be sped up by increasing the ethylene concentration in the atmosphere. Nothing fancy, nothing nefarious. No comment, however, on the fact that cheap supermarket tomatoes taste ... well, bland. That's a genetic change linked with why the tomatoes are slow to ripen in the first place.
PS - A couple of non-climacteric fruit: strawberries and most grapes. These do not continue to ripen post picking.