Yes and no. This sentence would indicate that this is an observation (that is, the devotees were actually present at the time of the surprise), so "had" would be more appropriate given that the observation is in the past. But "has" wouldn't be shocking, since one might assume that it still has many devotees if the observation was fairly recent, or if it is clear that the person speaking/writing is still in a position to know.
I was taught that a present tense verb (in this case "has") can be used only if it is a universal truth. For example, "The teacher said that the earth is round."
In my first sentence, there is no universal truth. Can the fact that there are many devotees at the temple be considered a truth and merit the use of "has'? In other words, besides a universal truth, a present tense verb can be used for a general truth.