I never understood just why Buffy saw any need in taking the others along when she tried to get away from Sunnydale. Spike, certainly, since, as she pointed out, besides her, he was the only one who had any chance of protecting Dawn from Glory. Willow had already proven that no amount of human generated magic would do more than make Glory mad, so she and Tara were useless, and it goes without saying that Xander and Giles would have been just one step beyond totally useless.
What Buffy SHOULD have done was to take Dawn and Spike in one direction, then send the others in two or more other directions, leaving false trails for Glory and at least increasing, if not assuring, her chances of getting away cleanly,while endangering her friends not one bit more than they were by all staying together. They might have even been safer, since the only way that the Knights of Byzantium were able to pose any problem whatsoever was because the RV was so slow. Horses, noble beasts that they might be, have no chance whatsoever of catching a speeding car, and without them being able to injure Giles, there would have been no reason to have to call Ben, which was the only way that Glory was able to find Dawn in the first place.
Honestly, if Joss would just ask me for advice before he makes these horrible blunders, Buffy's life would be much less complicated.