he is trying to make a sale and collect commission. trainers make almost nothing actually training at these gyms, they have to make it up other ways and hustle their way
it isn't true you need a protein shake. the supplement industry has spent billions putting out junk studies and copy/pasting them all over the place to convince people they need them. pros push them to rep. easy $$$. i have drank probably 3 or 4 in my lifetime and each time i felt like ass after. also protein powder is chemically processed crap. and most all of them have added artificials, dyes, and sugars/oils to make it 'taste good' . you might as well buy the cheapest ice cream from walmart and you would get the same nutrition, they are THAT BAD
choose real FOOD. your body is like a lambo, put in good fuel in it.