For a while, the angel is a tourist attraction. Although he doesn't do anything and is confused by all the attention, people demand to see him, touch him, and beg him for miracles; Peylayo and Elisenda take advantage of this and charge money, becoming wealthy. However:
...there arrived in the town the traveling show of the woman who had been changed into a spider for having disobeyed her parents.
A spectacle like that, full of so much human truth and with such a fearful lesson, was bound to defeat without even trying that of a haughty angel who scarcely deigned to look at mortals.
(Márquez,"A Very Old Man with Enormous Wings," salvoblue.homestead.com)
The spider-woman is seen as more interesting and a better attraction because she engages with the audience. While the angel may or may not have been divine in nature, he is unable to communicate and could not perform on command; he is scared and confused. The spider-woman can speak and the tourists feed it; it is a better show and a better story than an old man with wings who doesn't connect with people. The spider-woman also has a backstory, which is far more sympathetic than the old man's appearance in the mud.
This is an example of fickle human nature. As long as the angel was something new and exciting, the tourists were happy to see it even without any tangible results. As soon as something more interactive comes along, they switch their interest.