Spike gets a brimming full cup of blood from the fridge, but when he lifts it to his mouth and drinks, it is clearly almost empty.
Characters do not have voices, yet are able to gasp audibly and make some noises.
EXPLANATION: Voiceless sounds are those in which the vocal folds do not vibrate. Vowels are always voiced; some consonants are voiced, but many are not. Voiceless consonants ("t", "p", "k", etc) do not use the voice. They are percussive and use hard sounds. These sounds can be made by a person even if their vocal folds were removed or damaged; thus, a gasp or sigh (sharp in- or exhalation of air) can also be made without using voice.
In Something Blue (1999), Spike makes a fuzz over whether the blood he is given is warm enough, but is now perfectly happy to drink it straight from the fridge. EDIT: he was not perfectly happy, The look on his face was disappointment. Think of it like wanting a hot fresh slice of pizza, but settling for the left over cold slice in the fridge.
At 24:24, as the Gentlemen glide through the U.C. Sunnydale campus, you can see the rolling platform they are standing on.
At 22:46, in the wide side-view of the Gentlemen floating down the street, if you look closely you can see traces of the wires used to suspend them showing against the upper floors of the buildings in the background, and in the following shot the wires suspending the two Gentlemen floating in the distance are similarly visible against the roof at the right of the clock tower.
As the Gentlemen float along the dormitory hallways at 24:37 and 24:48, and again at 33:16, on the ceiling above them you can see part of the rigging from which they are suspended.
When Buffy and Willow are walking down the street, there is a group of people 'listening' to a priest. The woman next to him is holding a large blackboard with a biblical reference of 'Revelations 15:1.' The book of the bible is "Revelation" (it was only one revelation, after all).