Just found out Walgreens turned away someone trying to get their vaccine.

[Ms. Toad]

88. It may well be that there are not enough vaccinations on a daily basis

in that particular area to justify opening up a multi-vaccine vial.

In other words vaccine is only be available when there is a reasonable chance that the vial can be used fully used. In areas where there is a regular stream of walk-ins that may be on a daily basis. In areas where there are few walk-ins vaccine may not be available for walk-ins at all because of the need to use a full vial (rather than opening a vial for a single walk-in). If vaccines are scheduled for a specific narrow range of time, they can guarantee they are not throwing out vaccine. It would be perfectly reasonably to make vaccine available only in a way that they aren't wasting large quantities of it just to accommodate an occasional walk-in.

As for information about vaccines - I would expect it to be on the page dedicated to vaccines, not on the front page.