I don't know that the typical buyer has to pay the fee. The fee effectively (soft) caps the price at 1.05, but it may still trade much lower most of the time. Even if it trades a bit above $1, that's good for Hive in terms of economics, but it's a much smaller fee for buyers.
And some Sidenote: If it would be worth the 5% fee, we would see a massive run into HBD. 10% APR is really competitive
Not seeing that happening. For nearly all of the past 24 hours you could buy HBD for under $1, essentially a negative fee. It takes more than price to make something attractive.
If we start to see an equilibrium that is a bit over $1, then it would be a stronger case that the loose cap is constraining demand, but I don't see it yet.