I think most people will listen to advice, but are happiest if they make the final decision. I don't like a cushy, padded saddle, but my son and daughter both do. If I tried to impose my "better judgement" on them I think they'd be less likely to fall in love with their bikes and want to ride. Besides, they're not to the point of going on 40 mile training rides every weekend yet, like I enjoy. If they are happy on their 5 mile rides with their cushy saddles, good. If they ever get to the point of taking longer rides, maybe they'll come to the point where their saddles aren't comfortable, and might be willing to try something like what I use.
I think that's true of bikes too. My college-age daughter wanted a comfortable, upright bike, with a cushy saddle and a step-through frame. It had to be cute. She wanted to put a basket on it for shopping. Luckily, we found a Trek that has a lightweight frame, including suspension forks with a little bit of cushioning, a suspension seatpost, and a wide, cushy saddle. She mounted a "Toto" basket on the handlebar, a fold out set of shopping baskets in back, and she's happy with it. She usually just rides a few blocks to school or to the store. Good for her.
If the biking thing becomes more of a hobby, we'll consider something a little more "serious". If not, she's happy.