Additionally, rushing around someone with mobility issues or interfering with their cane/walker/wheelchair greatly increases the risk that they will trip, fall, or be otherwise injured.
If you are working in a place of business and a customer comes in using a cane/walker/wheelchair, be aware.
If you're the hostess at a restaurant and there's a long wait, try to find an extra chair if that person needs to sit down.
If you are escorting someone to their seat, be aware that they may move slowly or have difficulty maneuvering between tables/up stairs or ramps. Be patient, walk slowly, and try to clear the way if possible (tuck in chairs, etc.) It's always nice to ask if a booth or table is better (even if you're not generally offering the choice to people--sometimes it's difficult to get into/out of booths.)
If the person has a walker, offer to stow it for them in an out-of-the-way place--but make sure to bring it back later when they are ready to leave! Or make sure they/their companion(s) know where it is. Generally these people know that a walker in the aisle can be dangerous or difficult to work around, and are looking for a place to stow it if you don't offer.