I don't give unsolicited advice, but try to lead by example. In the case of the fees mentioned, I would probably just note offhand that low fees are important. If I knew the we weren't in a place for potential embarrassment and I cared about this person, I would note they should check to see if they're really getting a deal, as all of mine are under 1%. Otherwise if I cared, I would make a mention of it later in private. If I don't know or care about the person, I'm not sticking my neck out to see how they react. However, I don't see comparisons on a topic somebody brought up as unsolicited, and I'm not really giving advice, just a point of comparison.
That said, when people do come to me for advice, I'm honest and straightforward. Some friends take it to heart more than others. And it can be really difficult to see somebody take part of your advice and then go off in the wrong direction. Case in point, a friend that had various debts at some fairly unfavorable rates. He asked for advice and I suggested to roll it up into an unsecured personal loan at a lower rate and to pay it off as quickly as he could. He rolled everything up but instead went for a longer term to reduce the payment from what he had been able to pay monthly already so he could "free up cashflow" which he then spends monthly. He's still better for it because he'll still pay less in interest and he's not putting that additional amount on credit, so I'm happy I could help, but still. He could be saving something instead of just trying to get back to zero. After years he may be coming around, though, as he mentioned he had a savings goal very recently.
I guess the point of that longwindedness is to be careful with your advice. I've never admonished my friend for his choices, just tried to shed light on the path forward. Lead by example, give advice when asked and without being attached to the outcome, and eventually people may come around.