The Bellhop / Bellboy
This position is a relic from a previous era. Originally, an older child or very young adult would fill this entry level position. The Desk clerk would ring a bell to summon them, and they would "hop" to it, hence the name. They were general labor, lugging, carting, and escorting, delivering messages and packages, and erranting on demand. Pay was poor. In some regions, the bellboy would also be a local urchin, and thus would have a wide ranging street knowledge, which the hotel and/or patrons could leverage to find good deals or discounts (usually relatives or friends), special services, and lesser known sites worthy of visiting. This 'extra knowledge' or 'local tips' was often rewarded by grateful patrons with change and spare cash. Frequent customers (or those that tipped well) would find that their reputation would spread and service could be decidedly faster and of higher quality than otherwise.
The Bellhop position clings to existence in certain high-end hotels, while other positions from the same era have fallen by the wayside as culture and economics have changed over time: The elevator operator, the "pit crew" at gas stations, the doorman, the butler, room service (food), shoeshine boys, newsies, and more. Some of these positions can still be found here and there, but are much less common with automation, changing values and culture and economics.
The media has long glamorized the generously tipping high roller, which may have something to do with the wide spread of the tipping phenomena in American culture. Even to this day, certain types of service staff (waiters, mostly) are paid significantly less in anticipation of their receiving tips; an ongoing debate and challenge.
In modern America, it is not considered impolite to refuse the service, if you can find it, and it is much less likely that they will be highly knowledgeable locals. In fact, it is increasingly rare to run into an establishment that has any. I don't know of any in my immediate area, nor the last four or five places I have lived in. Unless you are in the habit of frequenting really expensive places to stay, or are in a large city where competition drives the service, you are not likely to find one.
On the flip side, if they do happen to be a local with street knowledge, getting on their good side can only benefit you.
How to guarantee not meeting a bellhop
Call the hotel and ask if they provide that service prior to your booking a room at that hotel.