Not only that, the banks don't have to pay the bond/mortgage originator a commission.
Plus you get a chance to negotiate a rate face to face with the bank/s.
It's as you say, people are generally lazy, like sheep, and it ostensibly appears to be too much trouble to fill in the forms at 4-5 banks, so they go to a bond originator. Somehow they are convinced and believe that the bond originator has their best interest at heart.
Nothing could be further from the truth, the bond originator works for themselves, first and foremost. They are an intermediary, they "wet their suckers" in a direct ratio to the amount of business that they commit to bringing in to the bank. So at the outset, before any sheep apply for a loan, the deck is already loaded, the pap has been eaten, the embers of the fire have died down, and the (stuffed) piggies and leeches are slumbering.
The bond originator needs to meet their quota, so the next step is for the leech to convince the sheep that they are the good guys, that they will "fight" for the best interest rate for them. They don't tell the sheep the truth: that they have a long-term working relationship with all of the piggies (who run the banks), based on their performance, that spans many years. Their relationship with the sheep is short term by comparison. It isn't in their best interest to "fight" with the piggies at the bank, because these are the same piggies that feed them.
The leeches convince the sheep that it is better to deal with them. Their value proposition is based on the lazy nature of the sheep, the sheep buys into the leech's business model, primarily because the sheep is far too lazy to fill out a 4 page form for each piggy (and submit the countless evidences, which are actually all the same).
Practically speaking, the model is flawed from the outset, just like BBBEE. An intermediary (or intermediaries / leeches) who actually add next to zero value to the procurement process, convince the sheep that it is in their best interests to use their "services" and once convinced, can wet their suckers a few times and then move on to their next victim. Welcome to the parasitic world of bond / mortgage originators!