Some doctors ask parents to switch to formula before moving to cow's milk as the formula is easier to digest so if mom breastfed right up to going back to work or continues to breastfeed morning and night having formula would be the expectation for awhile. Besides if mom provides no issues as it saves you money. Some also switch to the new toddler formula's until their child is eating enough real foods too because of the added nutrients.

Is too much rich milk preventing eating real food - probably. I would probably get some infant cereal and start giving the child that to teach them to eat. In other words you may have to be the one that transitions the child from formula to foods going through all of the stages with cereal first and then adding some fruits and veggies, then meats etc.